REMOVAL & INSTALLATION
- Remove the air cleaner.
- Remove the throttle cable from the throttle lever.
- Label and detach all vacuum lines, emission hoses, the fuel line, electrical connection and the choke heat tube at the carburetor.
- Remove the carburetor retaining nuts and remove the carburetor.
- Remove the carburetor mounting gasket, spacer (if equipped) and the lower gasket from the intake manifold.
- Clean all gasket mounting surfaces and place the spacer between two new gaskets. Position the spacer and gaskets on the intake manifold.
- Position the carburetor on the spacer and gasket.
- Position and connect the choke heat tube.
- Install the spark and EGR vacuum lines (if so equipped) before bolting the carburetor in place.
- Install the carburetor attaching nuts to a snug position, then tighten in a crisscross pattern.
- Connect the fuel line, throttle cable and vacuum lines.
Efficient carburetion depends greatly on careful cleaning and inspection during overhaul, since dirt, gum, water, or varnish in, or on, the carburetor parts are often responsible for poor performance.
Overhaul your carburetor in a clean, dust-free area. Carefully disassemble the carburetor, referring often to the exploded views. Keep all similar and look-alike parts segregated during disassembly and cleaning to avoid accidental interchange during assembly. Make a note of all jet sizes.
When the carburetor is disassembled, wash all parts (except diaphragms, electric choke units, pump plunger, and any other plastic, leather, fiber, or rubber parts) in clean carburetor solvent. Do not leave parts in the solvent any longer than necessary to sufficiently loosen the deposits. Excessive cleaning may remove the special finish from the float bowl and choke valve bodies, leaving those parts unfit for service. Rinse all parts in clean solvent and blow them dry with compressed air or allow them to air dry. Wipe clean all cork, plastic, leather and fiber parts with a clean, lint-free cloth.
Blow out all passages and jets with compressed air and be sure that there are no restrictions or blockages. Never use wire or similar tools to clean jets, fuel passages, or air bleeds. Clean all jets and valves separately to avoid accidental interchange.
Check all parts for wear or damage. If wear or damage is found, replace the defective parts. Especially check the following:
Throttle shafts and bushings are not included in overhaul kits. They can be purchased separately.
Carburetor overhaul kits are recommended for each overhaul. These kits contain all gaskets and new parts to replace those which deteriorate most rapidly. Failure to replace all parts supplied with the kit (especially gaskets) can result in poor performance.
Some carburetor manufacturers supply overhaul kits of three basic types: minor repair, major repair, and gasket kits. Basically, they contain the following:
Minor Repair Kits:
Major Repair Kits:
After cleaning and checking all components, reassemble the carburetor, using new parts and referring to the exploded views. When reassembling, make sure that all screws and jets are tight in their seats, but do not overtighten,as the tips will be distorted. Tighten all screws gradually, in rotation. Do not tighten idle mixture needle valves into their seats: uneven idling will result. Always use new gaskets. Always adjust the float for correct drop and level.Motorcraft 5200 and 6500 Feedback Carburetors
During disassembly operations, refer to the exploded view of the components which accompanies this information. Keep the parts from the different sections of the carburetor separated. Clean and inspect all components. Wash components (except the accelerating pump diaphragm and any other rubber goods) in a suitable commercial solvent. Rinse all solvent-cleaned parts in kerosene to remove traces of the cleaning solvent, then dry with compressed air.
- Remove the float bowl cover screws and washers. Disconnect the choke rod by removing the plastic retaining bushings and remove the float bowl cover.
- Turn the bowl cover over and remove the choke rod seal, the float hinge pin, the float, fuel inlet needle and seat with gasket.
- Remove the three enrichment (power) valve vacuum diaphragm screws, washers and diaphragm.
- Remove the three vent cover/solenoid attaching screws and remove the cover.
- Pry the vent arm pivot pin toward the fuel inlet seat and remove the pin and vent arm.
- Remove the E-clip from the vent diaphragm stem, remove diaphragm assembly, vent spring, retainer and valve.
- Remove the choke cover housing retaining screws; remove the ring, housing and electric heater assembly.
- Remove the choke housing assembly mounting screws-note from where the different length screws come. Slip the housing away from the carb body and disengage the fast idle rod. Remove the O-ring gasket from the vacuum passage.
- Remove the choke shaft nut and washer, choke lever, fast idle cam, fast idle lever screw and fast idle lever spring.
- Remove the choke diaphragm cover screws, the cover, return spring, diaphragm and rod assembly.
- Remove the four accelerator pump-to-body screws and pump cover assembly. Remove the pump diaphragm and return spring.
- From the center of the main body of the carburetor remove the accelerator pump discharge screw assembly, pump discharge nozzle and two gaskets. Cover the main body with your hand, invert it and catch the two pump discharge balls as they free the discharge passage.
- Remove the primary high speed bleeds and main well tube and the secondary high speed bleeds and main well tube. Be sure to note the sizes of the air bleed plugs and main well tubes so they may be reinstalled in the proper position.
- Remove the primary and secondary main metering jets. Note the different size jets and their proper locations.
- Remove the power valve and gasket. Remove the secondary idle jet retainer and jets located on the side of the carburetor body.
- Turn the idler limiter cap in (clockwise) to the stop. Remove the limiter cap. Count the turns required to lightly seat the idle adjustment needle. Count to the nearest 1 / 16 turn. Remove the needle and spring.
- Remove the secondary throttle operating lever return spring. Remove the primary throttle shaft nut, lockwasher, flat washer and accelerator pump cam. Remove the idle speed screws and spring from the throttle shaft lever.
- Install the idle speed screw and spring. Install the accelerator pump cam, flat washer, lockwasher and nut on the primary throttle shaft.
- Install the idle mixture adjusting screw. Turn the screw in until it gently bottoms. Back out the needle screw the exact number of turns recorded when you disassembled it. Install a new limiter cap with its stop resting on the lean side of the stop on the carb body.
- Install the idle jet and retainer assembly on the secondary side. Install the power valve gasket and power valve. Install the primary and secondary main jets, primary and secondary main well tubes and high speed bleeds.
Be sure they are reinstalled in the correct place.
- Install the two accelerator pump discharge check balls. Install the pump discharge nozzle and the two gaskets. Install the accelerator pump discharge screw.
- Install the accelerator pump return spring, pump diaphragm and cover. Start the four pump cover screws and, holding the pump operating lever slightly opened to align the diaphragm gasket, tighten the four screws evenly.
- Install the automatic choke diaphragm adjusting screw. Adjust the screw so that the threads are flush with the inside of the cover. Install the choke diaphragm and rod assembly, the return spring and cover. Install the cover screws and lockwashers.
- Install the fast idle adjusting screw and spring on the fast idle arm. Install the flat spacer, fast idle arm and attaching screw. Install the choke shaft into the housing and position the fast idle cam on the housing post. Install the choke lever, lockwasher and nut.
- Place a new O-ring washer on the vacuum passage. Install the fast idle rod with the end with one tab in the fast idle adjusting lever and the other end in the long leg of the housing. Install the retaining screws.
- Adjust the choke plate pull down. Refer to the adjustment information of this section.
- Install the electric choke heater, housing, retaining ring and attaching screws. Index the housing and tighten the screws.
Be sure that the choke plate is in the full closed position before installing the electric choke heater element.
- With fuel bowl cover inverted, install bowl vent diaphragm, vent valve, spring, retainer and E-clip. Position vent arm and install vent arm pivot pin. Install vent valve cover/solenoid with the three retaining screws and tighten them.
- Install the needle seat and gasket. Install the power valve vacuum diaphragm. Depress the spring and install the screws and washers to finger-tightness. Hold the stem so the diaphragm is horizontal and tighten the screw equally.
- Install the float needle clip on the float tab, position the float and needle, install the needle into the seat and secure the float with the float pivot shaft.
- Adjust the dry float setting and the float drop. Refer to the adjustment information in this section.
- Install the choke rod seal. Install the choke rod and fasten it to the choke lever. Install the retaining clip.
- Place the bowl cover gasket in position, install the choke link into position on the choke lever and install the retaining clip.
- Place the float bowl cover in position and install the retaining bolts. Tighten them evenly.
- Install the throttle positioner.
During the disassembly operations, refer to the exploded view of components which accompanies this information.
- Separate the throttle connector rod retainer from the choke connector rod and remove the rod from the fast idle link.
- Remove the automatic choke components, including housing retaining screws, housing assembly, housing gasket and baffle plate, trip lever and pin assembly and fast idle link.
- Remove the air horn retaining screws, the dashpot and bracket, and the air horn and air horn gasket from the carburetor main body.
- With the air horn assembly inverted, remove the float pin and the float and lever assembly.
- With the air horn assembly turned upright, catch the needle pin, spring, needle and seat. Remove the float needle seat and gasket.
- Remove the air cleaner bracket and the choke plate retaining screws. If necessary, the ends of the screws may be filed and new screws used during assembly. Remove the choke plate.
- With the fast idle cam spring disengaged from the cam spring lever on the choke piston lever and shaft assembly, rotate the choke shaft and piston assembly in the counterclockwise direction until the choke piston is withdrawn from the choke piston cylinder. Remove the choke assembly from the air horn and remove the piston pin, piston, fast idle cam and spring from the piston lever and shaft assembly.
- With the main body casting inverted, catch the accelerating pump check needle as it falls out.
- With the throttle shaft arm spring disconnected, loosen the throttle shaft arm screw and remove the arm and pump connector link.
- Remove the retaining screws of the accelerating pump diaphragm housing and withdraw the diaphragm assembly, lifter link, metering rod and fuel bowl baffle plate as a unit.
- Separate the metering rod arm spring from the metering rod and remove the metering rod from the assembly.
- Compress the upper pump spring and remove the retainer. Lift off the upper spring and remove the metering rod arm assembly and pump lifter link from the diaphragm shaft.
- Compress the lower spring and remove the spring retainer, spring and pump diaphragm assembly from the housing.
- Use a special tool or a screwdriver of appropriate size to remove the low speed jet and metering rod jet.
- Remove the retaining screws which attach the throttle body flange to the main body casting and separate the components.
- Remove the gasket between the throttle body and main body.
- Filing the ends if necessary, remove the screws which retain the throttle plate (use new screws during assembly) and slide the throttle shaft and lever assembly out of the throttle body flange.
Do not remove the idle mixture limiter caps or the mixture screws from the throttle body.
- Prior to assembly, clean and inspect all components. Wash all components (except the accelerating pump diaphragm and the antistall dashpot assembly) in a suitable commercial solvent. Rinse all solvent-cleaned parts in kerosene to remove traces of the cleaning solvent, then dry with compressed air. Do not use wire or drills to clean openings in the carburetor-use of such devices will enlarge the hole or passage being cleaned, thus changing the operating characteristics of the carburetor.
- Install the throttle shaft and lever assembly to the throttle body flange, then position the throttle plate on its shaft so that the notch in the plate is lined up with the slotted idle port in the throttle body flange.
- Install the throttle plate retaining screws so that they are snug, but not tight. Move and rotate the shaft to ensure that the throttle plate does not bind in its bore and reposition the plate if necessary. Tighten the throttle plate retaining screws and stake or peen into place.
- Using a new gasket, join the main body casting with the throttle body flange and evenly tighten the retaining screws.
- Using the proper size screwdriver or special jet tool, install the metering rod jet and low speed jet.
- Install the pump diaphragm to the accelerating pump diaphragm housing and position the lower spring on the diaphragm shaft and housing.
- Install the spring retainer, pump lifter link, metering rod arm and spring assembly, and the upper spring on the diaphragm shaft.
- Depress the spring and install the upper retainer.
- Install the metering rod to the meter rod arm as shown in the illustration accompanying the preceding information.
- Line up the pump diaphragm with its housing and install the retaining screws. Position the fuel bowl baffle plate on the pump assembly and line up the pump housing, pump lifter link, metering rod and baffle plate with the main body casting.
Be sure that the vacuum passage in the diaphragm housing is lined up with that of the main body.
- Install the assembly to the main body casting, being sure that the pump lifter link is engaged with the main body, that the baffle plate has its grooves in the main body, and that the metering rod is inserted into the metering rod jet. Install the pump housing screws so that they are snug, but not tight. Pushing down on the diaphragm shaft to compress the diaphragm, tighten the retaining screws evenly.
- Adjust the metering rod.
- Install the throttle shaft arm and pump connector link to the throttle shaft and pump lifter link. Tighten the locking screw and connect the throttle shaft arm return spring.
- Install the fast idle cam and spring to the choke lever and shaft assembly.
- Install the choke piston and pin to the choke piston lever and shaft, then disengage the cam spring from the lever and install the choke shaft assembly to the air horn.
- Align the piston with the cylinder, rotate the shaft assembly in the clockwise direction until the piston pin is inside the cylinder. Position the cam spring on the cam spring lever of the choke lever assembly.
When the cam spring is properly positioned, the tangs on the cam and the choke lever will be lined up with one in front of the other.
- With the choke plate in position on the shaft, install the retaining screws without tightening fully. As with the throttle plate, move and rotate the shaft to ensure that the plate moves freely, then tighten the screws and peen or stake to secure.
- Install the needle valve seat and gasket in the air horn. Invert the air horn and install the needle, pin spring, needle pin, float and lever, the float pin.
- Adjust the float lever, and float pin. Adjust the float level.
- Install the pump check needle to the main body casting and position the air horn (with new gasket) and the antistall dashpot and bracket on the main body. Secure the dashpot bracket and evenly tighten the screws attaching the air horn to the main body.
- Install the choke trip lever and fast idle link to the choke housing. Be sure that the lever and link properly engage each other and the choke piston lever and shaft.
- Install the coil housing, gasket and baffle plate (with identification mark facing outward). The gasket should be between the baffle and the coil housing, and the thermostatic spring should engage the tang of the choke lever.
- Install the retainers and screws, set the housing to the proper setting, and tighten the screws.
- Install the air cleaner bracket and attach the throttle connector rod retainer to the fast idle link.
- Install the choke connector rod to the throttle lever and fast idle link.
- Secure the air horn to the main body and connect the connector rod retainer to the choke connector rod.
To help prevent damage to the throttle plates, use the EGR spacer, a carburetor stand, or some bolts, held in place by nuts, as a holding device while you are working on the carburetor.
- Remove the choke cover attaching screws, the retainer, bimetal cover and gasket.
- Remove the choke pulldown bracket screws (2), disconnect the vacuum hose from the carb body and remove the pulldown and linkage.
- Remove the fuel bowl vent cover (3 screws). Remove the cover, spring and gasket from the air horn. Note the position of the spring when you remove it. Remove the bowl vent attaching screw and lift the bowl vent assembly from its seat.
- Remove the fast idle cam, the choke lever retaining screw and the throttle return spring bracket. Remove the accelerator pump link, remember which slot it is located in for proper reassembly.
- Remove the remaining air horn screws (7) and remove the air horn. Place the air horn upside down and remove the gasket. Make sure all of the gasket material is cleaned from the gasket surface.
- A screw and a clamp attach the accelerator pump operating rod; remove them. Remove the pump spring retaining plate, rotate the pump rod and disconnect the pump drive spring and accelerator pump assembly. Do not put the pump plunger in carb cleaner.
- Rotate the pump operating rod and remove the rod and grommet from the bowl cover.
- The main well tube is not removable. Blow it out with air.
- Remove the choke housing (3 screws).
- Place your hand over the top of the main body and turn it upside down. The accelerator pump discharge weight and ball will be dislodged and fall in your hand. Retain them for reinstallation. Remove the fuel inlet valve and fitting, the float retainer, float shaft and float.
- Remove the main metering jet with a jet wrench. If you do not own or cannot borrow a suitable jet wrench, a 3 / 8 -inch deep slot screwdriver may be used.
- Remove the enrichment valve. A tool can be made for this purpose by taking a 3 / 8 inch wide screwdriver and grinding a 1 / 4 inch wide by 3 / 8 inch deep slot in the blade. The slot will provide the necessary clearance for the enrichment valve stem.
- Remove the hot idle compensator cover, the hot idle compensator valve, and the mounting gaskets from the main carb body.
- Remove the three screws that attach the throttle body to the main body; separate the two parts.
- Remove the low idle speed screw and the solenoid.
- Turn the idle mixture cap on the leanest position (clockwise). The limiter cap stop should be against the throttle body. Remove the limiter cap.
- Note the position of the idle mixture screw slot. Slowly turn the screw in until it lightly seats, record the number of turns required. Remove the idle mixture screw.
- Install the idle mixture screw into the throttle body. Lightly seat it and back off the number of turns recorded when you remove it. Position the slot in the screw head at the same point as recorded when you removed the limiter cap. Install a new limiter cap, lean stop against the throttle body.
- Install the low speed screw and solenoid. Position a new throttle body gasket on the main body and attach the throttle body. Before tightening the mounting screws, work the throttle several times to make sure it is not binding. Secure the mounting screws.
- Install a new hot idle compensator valve gasket and the valve in the carb main body. Place the cover and gasket over the valve and secure the attaching screws.
- Snap the small diameter end of the enrichment valve spring over the shoulder on the large end of the pin. Insert the pin into the valve body from the threaded end. Install the enrichment valve. Install the main metering jet.
- Install the hinge pin into the float arm and place the float into position. Install the hinge retainer and the fuel inlet valve with gasket.
- Make the dry float adjustment. Refer to the adjustment in this information.
- Install the accelerator ball and weight.
- Install the accelerator pump operating rod and grommet on the air horn. Push the accelerator pump cup over the retaining tab on the end of the pump piston rod. Assemble the pump spring and retainer plate to the piston rod. The larger end of the spring should contact the retainer plate and seat over the shoulder.
- While holding the accelerator pump assembly together, connect the pump operating rod through the slotted hole in the piston rod and rotate the rod so the plate can be positioned and the attaching screw installed. Tighten the attaching screw. Install the pump operating clamp and attaching screw.
- Put a new air horn gasket in position over the alignment pin. Guide the accelerator pump cup into the pump well and the main well tube into the main well in the carb body. Align the air horn and lower it into place. Make sure the enrichment valve stem squarely contacts the enrichment valve pin.
- Attach the air horn with seven screws. Hook the accelerator pump link to the pump operating rod and the correct slot in the throttle return spring bracket. Slide the throttle return spring mounting bracket assembly over the throttle shaft and align with the shoulders on the end of the shaft. Install the attaching nut and washer, engage the throttle return spring over the throttle stop.
- Engage the fast idle cam link in the fast idle cam slot. Install the cam, retainer, choke control lever and screw.
- Install the bowl vent assembly and hinge pin, secure with hinge pin screw. Place the small diameter of the bowl vent spring over the shoulder of the vent arm. Install the vent cover and gasket.
- Connect the choke pulloff linkage, install the bracket and reconnect the vacuum line.
- Install the bimetal choke, make sure the spring tab is engaged in the slotted choke shaft lever. Index the cover and tighten the mounting screws.
Be sure to use a new choke cap gasket.Motorcraft 2150 Carburetor
To facilitate working on the carburetor, and to prevent damage to the throttle plates, install carburetor legs on the base. If legs are unavailable, install four bolts (about 2 1 / 4 inches long of the correct diameter) and eight nuts on the carburetor base.
Use a separate container for the component parts of the various assemblies to facilitate cleaning, inspection and assembly.
The following is a step-by-step sequence of operations for completely overhauling the carburetor. However certain components of the carburetor can be serviced without a complete disassembly of the entire unit. For complete carburetor overhaul, follow all of the steps. To partially overhaul a carburetor or to install a new gasket kit, follow only the applicable steps.AIR HORN-DISASSEMBLY
- Remove the air cleaner anchor screw.
- Remove the automatic choke control rod retainer.
- Remove the air horn attaching screws, lockwashers and the carburetor identification tag. Remove the air horn and air horn gasket.
- Remove the choke control rod by loosening the screws which secure the choke shaft lever to the choke shaft. Remove the rod from the air horn. Slide the plastic dust seal out of the air horn.
- If it is necessary to remove the choke plate, remove the staking marks on the choke plate attaching screws and remove the screws. Remove the choke plate by sliding it out of the shaft from the top of the air horn. Remove any burrs around screw holes prior to removing the choke shaft out of the air horn.
- Disconnect the choke pulldown link by removing the rod retainer and pulling the rod out of the diaphragm link slot.
- Remove the two screws from the attaching bracket. Disconnect the vacuum supply tube and remove the pulldown diaphragm.
- Position the choke pulldown diaphragm mounting bracket against the main body casting and install the two attaching screws.
- Connect the vacuum supply tube to the correct vacuum base tube connection.
- Insert the choke pulldown control rod through the slot in the diaphragm link. Install the retainer clip over the end of the rod in the slot.
- Perform an automatic choke pulldown clearance and fast idle cam index setting adjustment as described at the end of this information.
- Remove the fast idle cam retainer.
- Remove the thermostatic choke spring housing retaining screws and remove the clamp, housing and gasket.
- Remove the choke housing assembly retaining screws. If the air horn was not previously removed, remove the choke control rod retainer. Remove the choke housing assembly, gasket and the fast idle cam rod from the fast idle cam lever.
- Remove the choke lever retaining screw and washer. Disconnect the choke control rod from the choke lever. Remove the choke lever and fast idle cam lever from the choke housing.
- With the use of a small prytool, pry the float retainer from the fuel inlet seat. Remove the float, float shaft retainer and fuel inlet needle assembly. Remove the retainer and float shaft from the float lever.
- Remove the fuel inlet needle, seat, filter screen and main jets with a jet wrench.
- Remove the booster venturi screw (accelerator pump discharge), air distribution plate, booster venturi and metering rod assembly and gasket. Invert the main body. Let the accelerating pump discharge weight and ball and the mechanical high speed bleed lift rod and spring fall into your hand.
- Remove the accelerator pump operating rod from the overtravel lever to the retainer. To release the operating rod from the overtravel lever retainer, press upward on the part of the retainer which snaps over the rod. Disengage the rod from the retainer and from the overtravel lever. Remove the rod and retainer.
- Remove the accelerating pump cover attaching screws. Remove the accelerating pump cover, diaphragm assembly and spring.
- If it is necessary to remove the Elastomer (power) valve, grasp it firmly and pull it out. If the Elastomer valve tip broke off during the removal, be sure to remove the tip from the fuel bowl. An Elastomer valve must be replaced whenever it has been removed from the carburetor, as it will dry out and crack.
- Invert the main body and remove the enrichment valve with a box wrench or socket wrench. Remove the enrichment valve gasket. Discard the gasket.
- Remove the idle fuel mixture adjusting screws (needles) and the springs. Remove the limiters from the adjusting screws.
- If necessary, remove the nut and washer securing the fast idle adjusting lever assembly to the throttle shaft and remove the lever assembly. If necessary, remove the idle screw and the retainer from the fast idle adjusting lever.
- Remove the anti-stall dashpot, solenoid or solenoid-dashpot (if so equipped).
- If it is necessary to remove the throttle plates, lightly scribe the throttle plates along the throttle shaft, and mark each plate and its corresponding bore with a number or letter for proper installation.
- Slide the throttle shaft out of the main body, making sure that you catch the mechanical high speed bleed actuator located on the throttle shaft between the throttle plates.
- Clean and inspect the carburetor components.
Make sure that all holes in new gaskets have been properly punched and that no foreign material has adhered to the gaskets. Make sure that the accelerating pump diaphragm is not torn or cut.
- Slide the throttle shaft assembly into the main body until it begins to enter the high speed bleed cam slot in the body.
- Holding the cam by the edge of the point, hold it in the slot and rotate the throttle shaft until it will pass through the cam. Rotate the shaft clockwise until the throttle lever clears the boss for the TSP "off" idle speed screw. Continue inserting the shaft into the proper position, rotating as necessary to properly position the cam.
- Refer to the lines scribed on the throttle plates and install the throttle plates in their proper location with the screws snug, but not tight. Always use new screws when installing throttle plates.
- Close the throttle plates. Invert the main body, and hold it up to the light. Little or no light should show between the throttle plates and the throttle bores. Tap the plates lightly with a screwdriver handle to seat them. Hold the throttle plates closed and tighten and stake the attaching screws. Stake hardened screws by crimping the exposed threads with diagonal cutters.
- If necessary, install the fast idle screw on the fast idle adjusting lever.
- Install the anti-stall dashpot, solenoid or solenoid-dashpot (if so equipped).
- Place the fast idle adjusting lever assembly on the throttle shaft and install the retaining washer and nut.
- If the Elastomer power valve was removed, lubricate the tip of the new Elastomer valve and insert the tip into the accelerator pump cavity center hole. Using a pair of needlenose pliers, reach into the fuel bowl and grasp the valve tip. Pull the valve in until it seats in the pump cavity wall and cut off the tip forward of the retaining shoulder. Remove the tip of the bow.
- Install the accelerating pump diaphragm return spring on the boss in the chamber. Insert the diaphragm assembly into position on the main body. Install the cover screws.
- Insert the accelerating pump operating rod retainer over the specified hole in the overtravel lever. Insert the operating rod through the retainer and the hole in the over-travel lever and snap the retainer down over the rod.
- Invert the main body. Install the enrichment valve and new gasket with a wrench. Tighten the valve securely.
- Install the idle mixture adjusting screws (needles) and springs. Turn the needles in gently with your fingers until they just touch the seat, then back them off 1 1 / 2 turns for a preliminary idle fuel mixture adjustment. Do not install the idle mixture limiters at this time. Install the enrichment valve cover and new gasket. The cover must be installed with the limiter stops on the cover in position to provide a positive stop for the tabs on the idle mixture adjusting screw limiters.
- Install the main jets and the fuel inlet seat, filter screen, baffle and new gasket. Be sure that the correct jets are installed.
- Install the fuel inlet needle assembly in the fuel inlet seat.
- Slide the float shaft into the float lever. Position the float shaft retainer on the float shaft.
- Insert the float assembly into the fuel bowl and hook the float lever tab under the fuel inlet needle assembly. Insert the float shaft into its guides at the sides of the fuel bowl.
- With a prytool, position the float shaft retainer in the groove on the fuel needle inlet seat. Check the float setting.
- Drop the accelerating pump discharge ball and weight into the passage in the main body.
- Position the new booster assembly gasket and the booster venturi assembly in the main body. Install the air distribution plate and the accelerator pump discharge screw. Tighten the screw.
- Position the fast idle cam lever on the thermostatic choke shaft and lever assembly. The bottom of the fast idle cam lever adjusting screw must rest against the tang on the choke lever. Insert the choke lever into the rear of the choke housing. Position the choke lever so that the hole in the lever is to the left side of the choke housing.
- Install the fast idle cam rod on the fast idle cam lever. Place the fast idle cam on the fast idle cam rod and install the retainer. Place the choke housing vacuum pick-up port to main body gasket on the choke housing flange.
- Position the choke housing on the main body and at the same time, install the fast idle cam on the hub on the main body. Position the gasket and install the choke housing attaaching screws. Install the fast idle cam retainer. Install the thermostatic spring housing.
- If the choke plate shaft was removed, position the shaft in the airhorn, then install the choke plate rod on the end of the choke shaft.
- If the choke plate was removed, insert the choke plate into the choke plate shaft. Install the choke plate screws snug, but not tight. Check for proper plate fit, binding in the air horn and free rotation of the shaft by moving the plate from the enclosed position to the open position. If necessary, remove the choke plate and grind or file the plate edge where it is binding or scraping on the air horn wall. If the choke plate and the shaaft move freely, tighten the choke plate screws while holding the choke in the fully closed position.
- Position the main body gasket and the choke rod plastic seal on the main body. Position the air horn on the main body and gasket so that the choke plate rod fits through the seal and the opening in the main body. Insert the end of the choke plate rod into the automatic choke lever. Install the air horn attaching screws and the carburetor identification tag. Tighten the attaching screws. Install the choke plate rod retainer. Install the air cleaner anchor screw. Tighten the air cleaner anchor screw to the specified torque.
Perform all automatic choke adjustments and other carburetor functions to specifications.Motorcraft Variable Venturi 2700VV
It will be easier and you will avoid damaging the carburetor if you make a carburetor stand out of four bolts. The following is a step-by-step procedure. However, many components can be serviced or replaced without completely disassembling the carburetor. Read the steps over carefully before you begin and you will probably save some time.
Special tools are required. Also, rebuilding kits include specific procedures. Read them carefully before attempting any carburetor overhaul.UPPER BODY
- Remove the fuel inlet fitting, fuel filter, gasket and spring.
- Remove the screws retaining the upper body assembly and remove the upper body.
- Remove the float hinge pin and float assembly.
- Remove the fuel inlet valve, seat and gasket.
- Remove the accelerator pump rod and the choke control rod.
- Remove the accelerator pump link retaining pin and the link.
- Remove the accelerator pump swivel and the retaining nut.
- Remove the E-ring on the choke hinge pin and slide the pin out of the casting.
- Remove the cold enrichment rod adjusting nut, lever and swivel; remove the control vacuum nut and regulator as an assembly.
- Remove the cold enrichment rod.
- Remove the venturi valve cover plate and roller bearings. Remove the venturi air bypass screw.
- Using special tool T77P-9928-A (or equivalent), press the tapered plugs out of the venturi valve pivot pins.
- Remove the venturi valve pivot pins, bushings and the venturi valve.
- Remove the metering rod pivot pins, springs and metering rods. Be sure to mark the rods so that you know on which side they belong. Also, keep the venturi valve blocked open when working on the jets.
- Using tool T77L-9533-B (or equivalent), remove the cup plugs.
- Using tool T77L-9533-A (or equivalent), turn each main metering jet clockwise, counting the number of turns, until they bottom in the casting. You will need to know the number of turns when you reassemble the carburetor. Remove the jets and mark them so that you know on which side they belong. Don't lose the O-rings.
- Remove the accelerator pump plunger assembly.
- Remove the idle trim screws. Remove the venturi valve limiter adjusting screw.
- To assemble the upper body, reverse the removal order.
- Remove the cranking enrichment solenoid and the O-ring seal.
- Remove the venturi valve cover, spring guide, and spring. Remove the venturi valve.
- Remove the throttle body.
- Remove the choke heat shield.
- Assembly is in the reverse order of the disassembly procedure.
- Remove the air cleaner.
- Disconnect the fuel and deceleration valve (if equipped) hoses from the carburetor.
- Remove the small clip that attaches the choke rod to the choke plate shaft and disconnect the rod from the shaft.
- Remove the screws that attach the upper body of the carburetor to the main body of the carburetor and carefully lift the upper body off the main body. Be careful not to tear the upper body gasket.
- Turn the carburetor upper body upside down and measure the clearance between the bottom of each float and the bottom of the carburetor upper body. The clearance should be 0.420 in. (No. 58 drill bit).
- If the clearance is incorrect, bend the float level adjusting tang to correct it.
Both floats must be adjusted to the same clearance.
- Install the upper body and gasket of the main body of the carburetor and connect the choke rod to the choke plate lever. Install the choke rod attaching clip in the hole in the rod.
- Install the upper body attaching screws.
- Connect the fuel and deceleration valve hoses to the carburetor.
- Install the air cleaner.
- Insert a 5 / 32 in. diameter drill bit between the lower edge of the choke plate and the air horn wall.
- With the fast idle screw held on the second step of the fast idle cam, measure the clearance between the tang of the choke lever and the arm on the fast idle cam.
- Bend the choke lever tang to adjust it, if necessary.
- Remove the choke thermostatic spring cover.
- Pull the water cover and the thermostatic spring cover assembly out of the way.
- Set the fast idle cam on the second step.
- Push the diaphragm stem against its stop and insert the specified gauge between the lower edge of the choke valve and the air horn wall.
- Apply sufficient pressure to the upper edge of the choke valve to take up any slack in the choke linkage.
- Turn the adjusting screw in or out to adjust the choke plate-to-air horn clearance.
- Turn the secondary throttle stop screw counterclockwise until the secondary throttle plate seats in its bore.
- Turn the screw clockwise until it touches the tab on the secondary throttle lever, then add 1 / 4 turn.
For electric choke procedures, refer to the 2150 carburetor information.FAST IDLE SPEED
- Remove the air cleaner assembly and plug the vacuum line at the source of vacuum.
- Set the parking brake and block the wheels.
- Connect a tachometer to the engine.
- Start the engine and allow it to warm up to normal operating temperature.
- Reinstall any distributor vacuum lines that were removed and check the ignition timing.
- Remove the EGR vacuum line at the valve and plug the line.
- If applicable, remove the spark delay valve and route the primary distributor advance vacuum signal directly to the primary distributor diaphragm (advance side). If the distributor has a secondary (retard) diaphragm, leave the vacuum connection intact.
- Disconnect and plug the fuel deceleration valve hose (if so equipped) at the carburetor connection.
- If equipped, turn the air conditioner off.
- With the engine running at normal operating temperature and choke plate fully opened (automatic transmission in Park and manual in Neutral) set the throttle so that the fast idle adjustment screw contacts the kickdown step of the choke cam and adjust the fast idle adjusting screw to obtain the specified rpm according to vehicle specifications.
- Set the throttle to the high step of the choke cam and allow the engine to run approximately 5 seconds.
- Rotate the choke cam until the fast idle adjustment screw contacts the kickdown step of the choke cam. After allowing the rpm to stabilize, recheck fast idle rpm and readjust if necessary by repeating Steps 10-12 until the specified fast idle speed is obtained and can be repeated.
- Stop the engine and install the air cleaner and vacuum lines.
California models of the Fairmont and Zephyr using the 4-cylinder, 2.3 liter, 140 cubic inch engine may be equipped with a Feedback Engine Control system. This system requires more precise fuel metering and is equipped with the Holley/Weber 6500 Feedback carburetor.
The Holley/Weber 6500 Feedback carburetor is basically a Model 5200 carburetor that has an externally-variable auxiliary fuel metering system in place of the usual enrichment valve.
For adjustment procedures, please refer to the 5200 carburetor procedures earlier in this information.FEEDBACK VALVE PISTON
If the feedback valve piston and diaphragm assembly is removed for any reason it is essential that the following procedure is followed during reassembly.
- Apply one drop of Loctite® 271 or equivalent to the threads of the retaining screw holes.
- Position the feedback fuel diaphragm and piston assembly over the spring, so that the attaching holes are aligned with the tapped holes in the air horn. Make sure the diaphragm spring is properly installed with one end of the spring over the end of the adjustment screw and the other centered within the cupped washer of the diaphragm and piston assembly.
- Install the three retaining screws and tighten to 4-5 inch lbs. (0.5-0.6 Nm).
AUTOMATIC CHOKE HOUSING
By rotating the spring housing of the automatic choke, the reaction of the choke to engine temperature can be controlled. To adjust, remove the air cleaner assembly, loosen the thermostatic spring housing retaining screws and set the spring housing to the specified index mark. After adjusting the setting, tighten the retaining screws and replace the air cleaner assembly to the carburetor.CHOKE PLATE PULL-DOWN CLEARANCE
- Remove the carburetor air cleaner and remove the choke thermostatic spring housing.
- Bend a section of 0.026 in. diameter wire at a 90° angle, approximately 1 / 8 inch from one end.
- Insert the bent end of the wire gauge between the choke piston slot and the right-hand slot in the choke housing. Rotate the choke piston lever counterclockwise until the gauge is snug in the piston slot.
- Exert light pressure upon the choke piston lever to hold the gauge in position. Check the specified clearance with a drill of the correct diameter between the lower edge of the choke plate and the carburetor bore.
- Choke plate pull-down clearance may be adjusted by bending the choke piston lever as required to obtain the desired clearance. It is recommended the choke piston lever be removed prior to bending, in order to prevent distorting the piston link.
- Install the choke thermostatic spring housing and gasket, and set the housing to the proper specification.
The float level is adjusted dry in the following manner: remove the carburetor air horn and gasket from the carburetor. Using a gauge made to the proper dimension, invert the air horn assembly and check the clearance between the top of the float and the bottom of the air horn. Float level is 3 / 8 inch. When checking the float level, the air horn should be held at eye level and the float lever arm should be resting on the pin of the needle valve. Bend the float lever arm to adjust the float clearance. However, do not bend the tab at the end of the float arm, as this will prevent the float from bottoming in the fuel bowl when the bowl is empty. Using a new gasket, install the carburetor air horn.METERING ROD
With the carburetor air horn and gasket removed from the carburetor, unscrew the idle speed adjusting screw until the throttle plate is tightly closed in the throttle bore. Press downward on the end of the diaphragm shaft until the metering rod arm contacts the lifter link at the diaphragm stem. With the metering rod in the preceding position, turn the rod adjustment screw (refer to the accompanying illustration) until the metering rod just bottoms in the body casting. Turn the metering rod adjusting screw one additional turn in the clockwise direction. Install the carburetor air horn along with a new gasket.DECHOKE CLEARANCE
- Remove the air cleaner.
- Hold the throttle plate to the full open position while closing the choke plate as far as possible without forcing it. Use a drill of the proper diameter (refer to the Specifications chart) to check the clearance between the choke plate and air horn.
- To adjust, bend the arm on the choke trip lever of the throttle lever. To decrease the clearance, bend the arm downward; to increase the clearance bend the arm upward. Recheck the clearance after making the adjustment.
- Position the fast idle screw on the kickdown step of the fast idle cam against the shoulder of the high step.
- Adjust by bending the choke plate connecting rod to obtain the specified clearance between the lower edge of the choke plate and the carburetor bore.
FAST IDLE CAM
Fast idle cam position adjustment is necessary to make sure the fast idle screw contacts the various steps of the fast idle cam at the proper time during engine warm-up. This adjustment can be made with the carburetor on the engine (with the engine OFF ) or with the carburetor removed from the engine.
- With the fast idle speed adjusting screw contacting the second highest step of the fast idle cam (kickdown step), move the choke plate toward the closed position with light pressure on the choke lever or choke plate.
- Check the fast idle cam setting using the specified size gauge or drill bit between the upper edge of the choke plate and the wall of the air horn.
- Bend the fast idle cam link to achieve the specified setting.
To fabricate a convenient bending tool, file a slot in the blade of a flat screwdriver just wide enough to slip over the 1 / 8 inch fast idle cam link. The tool can also be used in other applications where bending a similar rod for adjustment is required.ACCELERATOR PUMP STROKE
The accelerator pump stroke is pre-set at the factory and should not be adjusted to improve driveability.DECHOKE CLEARANCE
The dechoke feature provides a means of partially opening the choke plate during cold engine starts, even though the choke bimetal spring is holding it closed. By depressing the accelerator pedal fully, engines that may have become `flooded' or that have stalled due to excessive choke action can be cleared. To adjust the dechoke clearance, proceed as follows:
- With the engine OFF, hold the throttle in the wide open position.
- Insert the specified size gauge or drill bit between the upper edge of the choke plate and the inner wall of the air horn.
- With light pressure against the choke shaft lever, a slight drag should be felt as the gauge or drill bit is withdrawn.
- To adjust, bend the tang on the throttle lever until the correct opening is obtained. The tab can be bent with a pair of pliers or other suitable bending tool. Bending the tab upward will increase the dechoke clearance.
Adjust choke pulldown by bending the choke pulldown diaphragm connecting link. Use a gauge or drill bit of the specified diameter to check the clearance between the top of the choke plate and the air horn.DASHPOT
Adjust the dashpot by loosening the locknut and turning the dashpot in the bracket. The dashpot plunger must be fully collapsed. Use a feeler gauge to check the clearance between the plunger and the throttle pad.EXTERNAL FUEL BOWL VENT
Adjust the external fuel bowl vent with the carburetor installed on the engine and the ignition OFF, after having first adjusted the curb idle speed.
- Remove the air cleaner assembly.
- Disconnect the canister vent hose from the bowl vent tube on the air horn.
- Attach a hand operated vacuum pump (Rotunda 21-0014 or equivalent) to the bowl vent tube, using a 3 / 8 inch adaptor.
- Remove the three bowl vent cover screws located on the top of the air horn.
- Remove the bowl vent cover gasket and spring.
- Turn the vent adjusting screw (located on the nylon vent arm) clockwise until no more than 1 / 8 inch of the adjustment screw threads is visible above the vent arm.
- While operating the hand vacuum pump, gradually turn the adjusting screw counterclockwise 1 / 8 turn at a time until vacuum is indicated on the gauge, showing that the valve is closed. Release the vacuum and turn the adjusting screw 1 / 2 turn clockwise. Disconnect the hand vacuum pump and adaptor from the vent hose.
- Reconnect the canister vent hose and install the air cleaner assembly.
- Remove the carburetor upper body (air horn) assembly.
- With the upper body assembly removed, place a finger over the float hinge pin retainer and invert the main body. Catch the accelerator pump check ball and weight as they drop from the pump channel.
- Using a straight edge, check the position of the floats as shown in the illustration.
- For all non-California carburetors, the straightedge should just touch the lowest point on the float (toe) when held as pictured.
- For all California carburetors, the straight edge should just contact the step (or heel) of the float.
- Once the adjustment is correct, turn the main body right side up and check the float alignment. The float should move freely throughout its range without contacting the fuel bowl walls. If the float pontoons are misaligned, straighten by bending the float arms. Recheck the float level adjustment.
FLOAT LEVEL-WET ADJUSTMENT
- Run the engine to normal operating temperature, turn off the engine.
- Remove the air cleaner.
- Remove the air horn attaching screws and the carburetor identification tag. Leave the air horn and gasket in position on the carburetor main body and start the engine. Let the engine idle a few minutes, then remove the air cleaner stud and the air horn and gasket to provide access to the float assembly.
- While the engine is idling, use a standard depth scale to measure the vertical distance from the top machined surface of the carburetor main body to the level of the fuel in the fuel bowl. The measurement must be made at least a 1 / 4 inch away from any vertical surface to assure an accurate reading. The fuel level should be measured at the point of contact of the float with the fuel. To raise the fuel level bend the flat tab contacting the fuel inlet valve upward and downward to lower it.
- Install a new air horn gasket and install the air horn assembly.
- Install the air cleaner anchor stud and install the air cleaner.
The dry float adjustment is a preliminary fuel level adjustment only. The wet float adjustment must be made after the carburetor is mounted on the engine.
- With the air horn removed, the air float raised and the inlet needle seated, check the distance between the top surface of the main body (gasket removed) and the surface of the float.
- Depress the float tab to seat the fuel inlet needle.
- Measure near the center of the float around 1 / 8 inch from the free end.
- Bend the tab on the float to adjust.
- With the engine OFF, remove the air cleaner and make sure that the hold-down wingnut has not been overtightened and caused the A/C housing to interfere with the choke plate operation.
- Make sure that the vacuum hoses, solenoid, and electrical choke wires are properly connected.
- Check throttle system, choke plate, linkage and fast idle cam for freedom of operation.
- Disconnect the choke lead wire from the choke cap and connect a jumper wire between the choke cap terminal and the wire terminal. Start the engine.
- Connect a test light between the connector of the choke lead wire and ground. If the light glows, current is available to the choke cap. The choke cap should be replaced. If the light does not glow, connect the test light between the alternator stator and the choke lead wire. If the light glows, replace the lead wire. If the light does not glow, the problem lies in the engine electrical circuit.
The automatic choke has an adjustment to control its reaction to engine temperature.
- Remove the air cleaner.
- Remove the heater hose from the bracket (if so equipped).
- Loosen the thermostatic spring housing clamp retaining screws.
- Set the spring housing to the specified index mark and tighten the clamp attaching screws.
- Replace the heater hose and air cleaner assembly.
The Model 2150 2V carburetor is equipped with a choke pulldown diaphragm assembly. Vacuum is metered to the diaphragm through internal passages in the carburetor, through a connecting external tube. As the vacuum bleeds through the orifices in the carburetor, the choke diaphragm pulls the choke plate to the pulldown position.Choke Pulldown Check
- Set the throttle on the fast idle cam top step.
- Note the index position of the choke bimetallic cap. Loosen the retaining screws and rotate the cap 90 degrees in the rich (closing) direction.
- Manually force the pulldown control diaphragm link in the direction of the applied vacuum or apply vacuum to the external vacuum tube to activate the pulldown motor.
- Measure the vertical hard gauge clearance between the choke plate and the center of the carburetor air horn wall nearest the fuel bowl. Adjust the choke plate pulldown to specification by adjusting the diaphragm stop on the end of the choke pulldown diaphragm.
- Set the choke bimetallic cap to specification.
- Remove the EGR vacuum line and air cleaner and plug both vacuum lines.
- Check the ignition timing.
- Place the transmission in Neutral and engage the parking brake.
- Start the engine and bring to normal operation temperature.
- Remove the spark delay valve (if so equipped) and route part throttle vacuum signal directly to advance side of distributor. If the distributor is a dual diaphragm model, leave the manifold vacuum line connected to the retard side of the distributor.
- Set the throttle to the kickdown step on the choke cam and make sure the adjusting screw is against the shoulder of the kickdown step.
- Adjust the rpm to specifications.
The accelerator pump stroke has been preset at the factory for each particular engine and should not be readjusted. However if the rod has been changed from the specified hole it should be reset.
- Lift up the retaining clip and release the rod.
- Position the slip over the hole specified in the carburetor specifications chart and insert the operating rod through the clip and the overtravel lever. Snap the end of the clip over the rod to secure.
The design of this carburetor differs considerably from the other carburetors in the Ford line up, an explanation of the differences in both theory and operation is presented here. Complete adjustment and repair instructions are also included in this information.
In exterior appearance, the variable venturi carburetor is similar to conventional carburetors and, like a conventional carburetor, it uses a normal float and fuel bowl system. However, the similarity ends there. In place of a normal choke plate and fixed area venturis, the 2700VV carburetor has a pair of small oblong castings in the top of the upper carburetor body where you would normally expect to see the choke plate. These castings slide back and forth across the top of the carburetor in response to fuel/air demands. Their movement is controlled by a spring-loaded diaphragm valve regulated by a vacuum signal taken below the venturis in the throttle bores. As the throttle is opened, the strength of the vacuum signal increases, opening the venturis and allowing more air to enter the carburetor.
Fuel is admitted into the venturi area by means of tapered metering rods that fit into the main jets. These rods are attached to the venturis, and, as the venturis open or close in response to air demand, the fuel needed to maintain the proper mixture increases or decreases as the metering rods slide in the jets. In comparison to a conventional carburetor with fixed venturis and a variable air supply, this system provides much more precise control of the fuel/air supply during all modes of operation. Because of the variable venturi principle, there are fewer fuel metering systems and fuel passages. The only auxiliary fuel metering systems required are an idle trim, accelerator pump (similar to a conventional carburetor), starting enrichment, and cold running enrichment.
Adjustment, assembly and disassembly of this carburetor require special tools for some of the operations. These tools are available from your Ford dealer. Do not attempt any operations on the carburetor without first checking to see if you need the special tools for that particular operation. The adjustment and repair procedures given here mention when and if you will need the special tools.
Before making any adjustments with the engine running, set the parking brake and block the wheels. Make sure the engine is at normal operating temperature and that any power accessories are turned off.CURB IDLE SPEED
Adjust the curb idle speed as you would on a conventional carburetor. Check the emission control decal under the hood for the proper idle speed.INTERNAL VENT
This adjustment must be checked whenever the curb idle speed is adjusted. After you have set the curb idle, place an 0.010 feeler gauge between the accelerator pump stem and the pump operating link. Turn the adjusting nut until there is just a slight drag when the gauge is removed.COLD ENRICHMENT METERING ROD
This procedure requires special tools.
Remove the choke cap, after noting its position so that you will be able to return it to the correct setting. Install a dial indicator with the tip of the indicator on the top of the enrichment rod and adjust the dial to zero. The cold enrichment rod is seated by installing the stator cap as a weight. After installing the cap in place of the choke cap, raise it slightly and let it drop. This should seat the cold enrichment rod. The dial indicator should still read zero. If it does not, repeat the procedure. Remove the stator cap and reinstall it in the choke cap's original position. The index mark on the stator cap should be in the same relative position as the index mark on the choke cap. The dial indicator should now read to specification. If it does not, turn the adjusting nut clockwise to increase or counterclockwise to decrease rod height. Reinstall the choke cap in its original position.CONTROL VACUUM
You will need a tachometer, a vacuum gauge and some Allen wrenches for this adjustment. With the engine at curb idle and a tachometer hooked up, turn the venturi valve diaphragm adjusting screw clockwise until the valve is completely closed. Connect a vacuum gauge to the vacuum tap on the venturi valve cover. Turn the venturi bypass adjusting screw to reach the specified vacuum setting. Then, turn the venturi valve diaphragm adjusting screw counterclockwise until the vacuum drops to the specified setting. In order to get the vacuum to drop, you must quickly increase engine speed once or twice. After you get the vacuum right, check and reset the curb idle, if necessary.FAST IDLE SPEED
With the engine idling, EGR disconnected and the vacuum line plugged, make sure the fast idle lever is on the specified step of the fast idle cam. Turn the fast idle adjusting screw clockwise to decrease speed.IDLE TRIM
Ford states that idle trim is adjusted at the factory and not adjusted in service.FUEL LEVEL
Remove the carburetor upper body. Remove the old gasket and install a new one. Fabricate a gauge to the specified dimension. Turn the upper body upside down and place the fuel level gauge on the cast surface, not on the gasket. Measure the vertical distance from the cast surface to the bottom of the float. If it needs adjustment, bend the float operating lever away from the fuel inlet needle to decrease the setting and toward the needle to increase the setting.FLOAT DROP
You will need to fabricate a gauge for this adjustment, also. With the upper body in the upright position, measure the distance between the cast surface of the upper body and the bottom of the float. To adjust, bend the stop tab on the float lever away from the hinge pin to increase the setting, and toward the hinge pin to decrease the setting.CONTROL VACUUM REGULATOR (CVR)
The cold enrichment metering rod adjustment must be set before making this adjustment.
Cycle the throttle to set the fast idle speed cam and rotate the choke cap 180 degrees clockwise (rich). Press down on the CVR rod. It it moves downward, it is not seated and must be adjusted. To adjust, turn the rod clockwise until the adjusting nut just begins to rise. Then, turn the adjusting screw clockwise in 1 / 4 turn increments until the rod is fully seated (no down travel). Reset the choke cap to the original setting.HIGH CAM SPEED POSITIONER (HCSP)
Holding the throttle closed, place the HCSP in the corner of the specified cam step (counting the highest step as the first). Place the fast idle lever in the corner of the HCSP. Remove the diaphragm cover and turn the assembly clockwise until it just bottoms on the casting, then turn it back until the vacuum port and diaphragm hole line up. Reinstall the cover.CHOKE LINKAGE
There is no choke plate on the variable venturi carburetor. Therefore, no adjustments are possible or necessary.Motorcraft 7200VV Feedback Carburetor
California models of the Fairmont/Zephyr using the 255 cubic inch V8 engine are equipped with a Motorcraft 7200VV Feedback carburetor.
The Model 7200VV Feedback carburetor shares the same basic systems with the 2700VV (variable venturi) carburetor. However, the 7200VV carburetor's feedback system is controlled by an Electronic Engine Control system (EEC III). This system provides precise control of the air/fuel ratio, thereby, improving exhaust emissions, driveability and fuel economy.
Methods of testing the 7200VV carburetor and the EEC III system are possibly beyond the resources of the do-it-yourselfer. It, therefore, is suggested that you consult your Ford dealer or a qualified repair shop for any service or repair.