See Figures 1, 2, 3 and 4
The Holley 2300 and 2300C are used as the three, two-barrel high performance option on the 427 engine from 1967 through 1969. This configuration uses one 2300C as the primary carburetor and two 2300 models as the two secondary units. The two models differ in that the C model contains the choke, power, and accelerator pump systems while the straight 2300 does not. The C model is operated through conventional linkage while the two secondaries are vacuum actuated.
Adjust the idle-speed screw until it touches the throttle lever. Add 1 1 / 2 turns to obtain the preliminary adjustment.
Fast-idle adjustment on the primary carburetor is made as follows: crack the throttle, and with the choke closed, place the fast-idle lever against the top step of the fast-idle cam. Bend the fast-idle lever so that the specified opening of the throttle plate on the idle transfer slot of the carburetor is achieved.
See Figure 5
Position the car on a flat, level surface and start the engine. Remove the sight plugs and check to see that the fuel level reaches the bottom threads of the sight plug port. A plus or minus tolerance of 1 / 32 in. is acceptable. To change the level, loosen the fuel inlet-needle locking screw and adjust the nut. Clockwise lowers the fuel level and counterclockwise raises it. Turn the nut 1 / 16 of a turn for each 1 / 16 in. desired change. Open the primary throttle slightly to assure a stabilized adjusting condition on the secondaries. There is no required float drop adjustment.
Accelerator Pump-Primary Carburetor
See Figure 6
Secure the throttle plate fully open and depress the pump lever, fully. Gauge the distance between the pump lever arm and the spring adjusting nut. Turn the nut or screw to adjust. The slightest movement of the throttle lever will actuate the correctly adjusted pump lever.
Vacuum Break-Primary Carburetor
Secure the choke valve closed and restrain the vacuum break against its stop. Bend the break rod to achieve the specified measurement between the lower edge of the choke valve and the body.
Choke Unloader-Primary Carburetor
Fully open the throttle valve and secure it. Close the choke valve against the throttle shaft unloader tang and bend the choke rod to obtain the specified measurement between the lower edge of the choke valve and the body.
DISASSEMBLY & ASSEMBLY Primary Carburetor
- Remove the fuel bowl, metering body, and splash shield. Disconnect the vacuum break hose, remove the throttle body attachment screws, and separate the throttle body from the primary carburetor body.
- Remove the fuel inlet baffle, float hinge screws, and the brass float. Remove the needle and seat assembly lock screw, then back out the adjusting nut and remove the seat assembly.
- Remove the sight plug and gasket, fuel inlet fitting, filter, spring and gasket. Remove the accelerator pump cover, diaphragm, and spring.
- Check the accelerator pump inlet ball. If damage is evident, replace the bowl assembly.
- Remove the main metering jets, power valve, vacuum fitting, and the idle-mixture needles and screws.
- Remove the choke vacuum break, choke lever and fast-idle cam. Remove the accelerator pump discharge nozzle and its check valve.
- Reverse the above procedure to assemble.
- Remove the fuel bowl and metering block. Disconnect the secondary diaphragm housing from the throttle lever and separate the housing from the carburetor body.
- Remove the throttle body attaching screws and separate the throttle body from the main body. Remove the fuel inlet baffle hinge screws and plastic float.
- Remove the needle and seat assembly, sight plug, fuel inlet fitting, filter, and spring. Remove the metering body plate and gaskets. Remove the diaphragm cover and diaphragm.
- Reverse this procedure to reassemble.