Small Engine Troubleshooting Problems? Ask a Mechanic Now.
The CH is carbureted engine and uses a pulse fuel pump. So the only way fuel can enter the crankcase is through the needle valve and float of carburetor. Is the fuel tank above the carburetor? Do you have a fuel shutoff valve on the tank line? If you smell fuel from exhaust , you can have a cylinder that is not firing. Do a cylinder balance test on the engine. This is loosening the spark plug wires, and then with engine at idle, remove one spark plug wire at a time. If engine dies when either plug wire is removed, the opposite cylinder is not firing.
Th fuel in the oil can only get there while engine is shutoff. It will not get there while engine is running.
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