Trouble idling
- Thread starter kkalan
- Start date
This is a symptom of an air (vacuum) leak somewhere in the intake circuit. Check your carburetor where it attaches to the intake manifold or the gasket at the manifold to the cylinder.
Use a spray bottle with some water and lightly spray around those areas. A change in engine RPM will tell you what's leaking. Some will suggest using other liquids like carburetor cleaner, WD-40 or others but water will work and not leave a messy residue.
Any excess air entering downstream of the carb inlet will cause a lean condition which can result in a high idle.
Also check your throttle cable for smooth action. If there are sharp bends or kinks the throttle return spring might not be able to close the throttle slide back to the idle position due to the resistance in the cable. You can check this by removing the air cleaner and looking into the throat of the carb while twisting the throttle and allowing it to return to idle. You should be able to watch the barrel (slide) move up and down. It must close almost completely for the idle speed to decrease.
Good luck, let us know what you find.
Tom
Use a spray bottle with some water and lightly spray around those areas. A change in engine RPM will tell you what's leaking. Some will suggest using other liquids like carburetor cleaner, WD-40 or others but water will work and not leave a messy residue.
Any excess air entering downstream of the carb inlet will cause a lean condition which can result in a high idle.
Also check your throttle cable for smooth action. If there are sharp bends or kinks the throttle return spring might not be able to close the throttle slide back to the idle position due to the resistance in the cable. You can check this by removing the air cleaner and looking into the throat of the carb while twisting the throttle and allowing it to return to idle. You should be able to watch the barrel (slide) move up and down. It must close almost completely for the idle speed to decrease.
Good luck, let us know what you find.
Tom
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The kit supplied gaskets are not the best quality. You can buy automotive grade gasket material at any auto parts store. You can use the manifold as a template and cut your own gasket. Just be sure to open up the big center hole as well as the two for the fasteners.
You can also use a gasket sealer made for that purpose on the intake gasket as well as helping to seal the carburetor to the intake manifold.
Be sure to tighten the fasteners properly and that the flange is flat and lays flush against the cylinder.
Tom
