Carburetor: Service and Repair

NOTE: Idle mixture adjusting screws on this vehicle are sealed at the factory to prevent tampering. If it is necessary to adjust idle mixture, follow appropriate procedure for removal of concealment plugs and limiter pins.

Front Wheel Drive Models With Holley Carburetors
1. Remove carburetor from engine and mount in a suitable holding fixture.

Fig. 42 - Concealment Plug Removal:

2. On manifold gasket surface of carburetor, drill a 5/64 inch pilot hole in casting around idle mixture screw, Fig. 42.
3. Redrill hole to 1/8 inch, then insert a blunt punch into hole and drive out plug.
4. On 1981 models, insert a sharp punch into mixture screw access hole and remove roll pin.
5. Reinstall carburetor on engine using a new base gasket.

Front Wheel Drive Models With Mikuni Carburetor
1. Remove carburetor from engine and mount in a suitable holding fixture.

Fig. 43 - Concealment Plug Removal:

2. Drill a small hole in face of concealment plug, Fig. 43, then remove plug.
3. Using a small sharp punch, push roll pin out from gasket surface of carburetor.
4. Reinstall carburetor on engine using a new base gasket.

Rear Wheel Drive Models With 1 Bbl. Holley Carburetors
1. Remove carburetor from engine and remove throttle body from carburetor.
2. Mount throttle body in vise with mixture screws facing up. Protect gasket surfaces from vise jaws.
3. On 1981 models, remove roll pins:

Fig. 44 - Limiter Pin Removal:

a. Drill a 5/64 inch pilot hole in casting directly above roll pin, Fig. 44, then enlarge hole to 1/8 inch.
b. Drive roll pin out with a sharp punch.
c. On reassembly, install roll pin in bottom of casting leaving clearance for mixture adjustment.

Fig. 45 - Concealment Plug Removal:

4. Drill a 5/64 inch pilot hole from manifold side of throttle body, on a 45 angle toward concealment plug, Fig. 45, then enlarge hole to 0.120 inch.
5. Drive plug out of casting with a blunt punch.
6. Reassemble and install carburetor using new gaskets.

Rear Wheel Drive Models With 2 Bbl. BBD Carburetor
1. Remove carburetor from engine and remove throttle body from carburetor.
2. Mount throttle body in vise with mixture screws facing up. Protect gasket surfaces from vise Jaws.

Fig. 46 - Concealment Plug Removal:

3. On 1981 models, drill a 5/64 pilot hole in casting above each roll pin, Fig. 46, then enlarge holes to 1/8 inch:
a. Remove roll pins with a suitable punch
b. Redrill holes (using 1/8 inch drill) at a 45 angle toward concealment plugs.
4. On 1982 models, drill a 5/64 inch pilot hole in casting around each mixture screw on a 45 angle toward concealment plug, Fig. 46, then enlarge holes to 1/8 inch.
5. Drive out concealment plugs with a blunt punch.
6. Reassemble carburetor and install on engine using new gaskets.

Rear Wheel Drive Models With 4 Bbl. TQ Carburetor

1. Remove carburetor from engine and mount in vise with mixture screws facing up.

Fig. 47 - Concealment Plug Removal:

2. Drill a 5/64 inch pilot hole in side of casting around each mixture screw, on a 45 angle toward concealment plugs, Fig. 47, then enlarge holes to 1/8 inch.
3. Drive concealment plugs from casting with a blunt punch.
4. On 1981 models, insert a sharp punch through mixture screw access hole and remove roll pins. On reassembly, install roll pins in bottom of casting, leaving clearance for mixture adjustment.
5. Reinstall carburetor on engine using a new base gasket.