REMOVAL & INSTALLATION
See Figures 1, 2 and 3
When removing the carburetor on 2.2L engines, it should not be necessary to disturb the isolator (check it for cracks), unless it has been determined that there is a leak in it.
- Disconnect the negative battery terminal. Allow the engine to cool thoroughly.
- Remove the air cleaner.
- Remove the fuel filler cap.
- Position a clean coffee can or similar metal container to catch fuel when the lines are disconnected. Detach the fuel inlet line and all necessary wiring from the carburetor.
It is necessary to drain the coolant on the 2.6L engine before removing the coolant lines at the carburetor.
- For 2.6L engines, drain the cooling system until the level of coolant is below the carburetor. For more information on draining the engine coolant, refer to Routine Maintenance . Disconnect the coolant lines from the carburetor.
- Disconnect the throttle linkage and all vacuum hoses from the carburetor.
- Remove the mounting nuts and lift the carburetor off of the isolator (carburetor-to-intake manifold adapter) and intake manifold. Hold the carburetor level to avoid spilling fuel from the bowl.
- Drain the fuel from the carburetor bowl into the fuel can used earlier.
- Clean the carburetor, isolator and, if the isolator was removed, the intake manifold gasket surfaces.
- Lightly lubricate the carburetor mounting studs and nuts with clean engine oil or a spray lubricant.
- Along with a new gasket, position the carburetor onto the isolator and mounting studs. Make sure that the carburetor is mounted facing the proper direction.
- Install and tighten the carburetor mounting nuts evenly until secure.
- The remainder of installation is the reverse order of removal.
- Start the engine and make all necessary carburetor adjustments, as described earlier in this section.
- Road test the vehicle for proper operation.
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 and directions packaged with the rebuilding kit. 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 is necessary to sufficiently loosen the deposits. Excessive cleaning may remove the special finish from the float bowl and choke valve bodies, leaving these 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 part 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 valve 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 may 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 later.
Some carburetor manufacturers supply overhaul kits of three basic types: minor repair; major repair; and gasket kits. Basically, they contain the following:Minor Repair Kit-
Major Repair Kit-
After cleaning and checking all components, reassemble the carburetor, using new parts and referring to the exploded view. 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 needle valves into their seats; uneven jetting will result. Always use new gaskets. Be sure to adjust the float level when reassembling.Holley Models 5220/6520
See Figures 4 through 25
- Remove the carburetor from the engine, as described earlier in this section.
- Disconnect and remove the choke operating rod and choke rod seal.
- Remove the 2 solenoid retaining screws and remove the solenoid from the carburetor.
- Remove the vacuum control valve and filter assembly.
- Remove the wiring clip from the top of the carburetor.
- On 6520 models, remove the 2 oxygen feedback solenoid retaining screws and gently lift the solenoid from the air horn.
- Remove the clip securing the vacuum control rod to the link, remove the vacuum control mounting screws and the vacuum control diaphragm.
- Remove the 2 Wide Open Throttle (WOT) cut-out switch mounting screws. Mark the switch location for proper reassembly. Remove the harness mounting screws and open the retaining clip.
- Remove the 5 air horn mounting screws and separate air horn assembly from the carburetor body.
- Remove the float level pin, float and float inlet needle.
- Remove the fuel inlet seal and gasket.
- Remove the main secondary metering jet. Be sure to note its size so that it can be reinstalled in its proper position.
- Remove the main primary metering jet. Be sure to note its size so that it can be reinstalled in its proper position.
- Remove the secondary high speed bleed and secondary main well tube. Be sure to note its size so that it can be reinstalled in its proper position.
- Remove the primary high speed bleed and primary main well tube. Be sure to note its size so that it can be reinstalled in its proper position.
- Remove the discharge nozzle screw, discharge nozzle and gasket.
- Invert the carburetor body and remove the accelerator pump discharge weight ball and check ball (both balls are the same size).
- Remove the 4 accelerator pump cover screws. Remove the cover, accelerator pump diaphragm and spring.
- Note the position of the accelerator pump arm pivot pin. If the pin is removed it must be reinstalled in its original position.
- Remove the 3 choke diaphragm cover screws. Remove the cover and spring.
- Rotate the choke shaft and lever assembly counterclockwise. Rotate the choke diaphragm assembly clockwise and remove it from the housing. Remove the end of the lower screw from the housing. If the choke diaphragm is to be replaced, the diaphragm cover must also be replaced.
- Remove the concealment plug and remove the idle mixture screw from the carburetor body.
- Clean all parts as described previously.
- If the entire choke assembly was removed, position it on the carburetor and install the 3 retaining screws. If the choke diaphragm was serviced, rotate the choke shaft counterclockwise. Insert the diaphragm with a clockwise motion. Position the spring and cover over the diaphragm and install the retaining screws.
Make certain the fast idle link is installed properly.
- Install the accelerator pump spring, diaphragm, cover and screws.
- Install the accelerator pump discharge check ball into the discharge passage. Check the accelerator and seat prior to assembly by filling the fuel bowl with clean fuel. Hold discharge check ball down with a small brass rod and operate pump plunger by hand. If the check ball and seat are leaking, no resistance will be experienced when operating plunger. If the valve leaks, stake the ball using a suitable drift punch. Exercise care when staking the ball to avoid damaging the bore containing the pump weight. After staking the old ball, remove and replace it with a new ball from the overhaul kit. Install the weight ball and recheck for leaks.
- Install new gaskets, discharge nozzle and screw.
- Install the primary main well tube and primary high speed bleed.
- Install the main well tube (secondary) and high speed bleed (secondary).
- Install the main metering jet (primary) on this assembly, the primary main metering jet will have a smaller number stamped on it than the secondary main metering jet.
- Install the secondary main metering jet (on this assembly, the secondary main metering jet will have a larger number stamped on it than the primary main metering jet.
- Install the needle and seat assembly.
- Invert the air horn and insert a 0.480 in. diameter gauge, drill bit, or equivalent between the air horn and the float.
- Using a pair of small, bent needle nose pliers, bend the tang to adjust the dry float level.
- Position a depth gauge and check the amount of float drop.
- Using a small pair of bent needle nose pliers, bend the tang to adjust the float drop to 1 7 / 8 inch (47.6mm).
- Position a new gasket on the air horn and install a new choke rod seal and choke operating rod.
- Carefully position the air horn onto the carburetor body. Install a new choke operating rod retainers onto the choke shaft lever and fast idle cam pick-up lever, then connect the choke operating rod.
- Install and tighten the 5 air horn-to-carburetor body screws, in even stages, to 30 inch lbs. (3.4 Nm).
- Install and tighten the solenoid screws until snug. Reinstall the anti-rattle spring.
- Install WOT cut-out switch; move the switch so that the A/C clutch circuit is open when the throttle is positioned 10° before WOT.
- On 6520 models, position a new oxygen feedback solenoid gasket onto the air horn. Install a new O-ring seal on oxygen feedback solenoid. Lubricate the O-ring seal with white grease and carefully install the solenoid into the carburetor body. Install and tighten the mounting screws securely.
- Install the vacuum solenoid.
- Install the vacuum control valve.
- Install and tighten harness mounting screws.
See Figures 26 through 47
- Pull the water hose off of the nipple of the throttle body and off the nipple of the wax element portion.
- Remove the throttle return spring and the damper spring.
- Grind down the head of the choke cover lockscrews by using a hand grinder or similar tool, then remove the choke cover.
- Remove the throttle position sensor.
- Remove the throttle opener/dash pot rod from the free lever, then remove the throttle opener/dash pot from the float chamber cover.
- Remove the harness from the carburetor electrical connector.
- Remove the solenoid valves for the deceleration, enrichment and jet mixture from the float chamber cover.
- Remove the bowl vent solenoid and valve.
- Remove the vacuum hose from the depression chamber and the throttle body.
- Remove the choke breaker cover.
- Remove the depression chamber rod from the secondary throttle lever, then remove the depression chamber.
- Remove the accelerator pump rod from the throttle lever.
- Remove the snapring from the choke rod, then disconnect the choke rod from the choke lever.
- Remove the float chamber cover screws B and remove the throttle body.
- Remove the screws A and remove the float chamber cover from the main body.
- Pull off the pin and remove the float and the needle.
- Unscrew the retainer and remove the needle seat with a pair of pliers. When removing the needle seat, clamp portion (A) with the pair of pliers. Do NOT clamp section (B) of the needle seat.
- Remove the main jets from the jet blocks. When the main jet is to be removed, use a screwdriver with a properly-sized blade for the slot in the jet, otherwise the jet could become stripped in the jet block.
- Remove the pilot jet retainer and pull out the secondary pilot jet with pliers.
- Remove the two lockscrews and remove the choke pinion assembly.
- Remove the check weight and ball, then remove the steel ball of the anti-overfill device.
- Remove the accelerator pump mounting screws and remove the pump cover-link assembly, diaphragm, spring, body and gasket from the main body.
- Remove the snapring from the sub-EGR control valve pin.
- Remove the pin, then remove the link from the valve. Take out the little steel ball and spring from the sub-EGR control valve.
- Remove the sub-EGR control valve from the throttle body.
- Clean all parts prior to reassembly, as described previously in this section.
- Check to be sure that no clogging is in the air passages and fuel passages of the carburetor body and related components.
Perform reassembly in reverse of disassembly procedure, paying special attention to the following items:
Check for smooth operation of the throttle and choke linkage. If the operation is not smooth, clean them or replace them at this time to ensure proper carburetor performance.
- Install the carburetor on the engine.
- Perform the carburetor adjustments, as described earlier in this section.
- Road test the vehicle for proper operation; readjust the carburetor, if necessary.