General description
1. The deceleration control system gradually closes the throttle so that excessively unburned fuel is not thrown into the exhaust, giving an increase in emissions.
2. The details of this system are flame arrester valve and (on models with manual transmission) shock absorber on the carburetor that controls the throttle.
3. A sign of damage in the shock absorber is the immediate closing of the throttle when decelerating. Failure of this valve may backfire and operate with the ignition off.
Component check
Flame arrester valve
4. Start the engine and place your hand under this valve.
5. Increase the engine speed to approximately 3000 rpm and then suddenly release the throttle. If the air coming from the valve is cut off, then it works correctly.
6. Let the engine idle. Disconnect the air hose from the valve and cover the open end of the hose. If the idle speed is very different from the frequency before the hose was disconnected, then the valve will leak and should be replaced.
Checking the flame arrester valve
Shock absorber
7. Quickly move the throttle lever away from the shock absorber and check that the shock absorber rod moves freely. Release the throttle, lift up and check that it slowly returns to its original position after contact with the shock rod.
8. To adjust the shock absorber, start the engine and idling at normal temperature, connect the tachometer. Slowly increase the engine speed and check that the damper bar separates from the lever at approximately 2200 rpm. Loosen the locknut and turn the damper to adjust it.
9. If the adjustment does not bring the shock absorber as given in the Specification, replace it with a new one.
Shock absorber and related parts (Chapter 7)
Replacement Parts
Flame arrester valve
10. Remove the air hose and snap off the valve from the suspension.
11. Install new valve and hanger and reattach air hose.
Shock absorber
12. Loosen the locknut and unscrew the shock absorber from the suspension.
13. Install new shock absorber and adjust as described.