Publication #81-370-6010

TSB 14-04-87 May 4, 1987 Publication #81-370-6010



5. ACCELERATOR PUMP STROKE MEASUREMENT 6280 MODELS
(1) Remove bowl vent cover plate and gasket.
(2) With pump links and levers installed, adjust the throttle blades to the closed position by backing out the idle speed screw.
(3) Set the distance from the top of pump lever to the top of bowl vent cover surface to .180" +/- .010" by bending the pump link. Check that wide open throttle can be reached without binding.
(4) Install gasket and bowl vent cover plate.
(5) Reset Idle Speed.



6. IDLE SPEED ADJUSTMENT

Before checking or adjusting any idle speed, check ignition timing and adjust if necessary using the procedure shown in Group 8 Electrical. Disconnect and plug the vacuum hose at the EGR valve and [1][2]air switching valve. Also disconnect and plug the vacuum hose from the carburetor at the heated air temperature sensor. Remove the air cleaner and disconnect and plug the 3/16 inch diameter control hose at the canister. Remove the PCV valve from the cylinder head cover and allow the valve to draw underhood air. Install tachometer. Start and run engine until normal operating temperature is reached.

RPM Refer to VECI Label

(1) Allow the engine to run for one minute for the engine speed to stabilize.
(2) If the engine rpm is not correct, turn the idle speed screw to obtain the correct idle rpm.
(3) Turn off engine. Unplug and reconnect vacuum hoses at EGR valve, canister, and [1][2]air switching valve.
(4) Reinstall air cleaner and unplug and reconnect vacuum hose from carburetor to heated air temperature sensor on air cleaner. Remove tachometer and reinstall PCV valve. Idle speeds with the engine in normal operating condition (all hoses and wires connected) may vary from set speeds. DO NOT READJUST.