Check your governor and linkage for build up of dirt and grime. You should be able to move the governor by hand, with some resistance from the springs. The governor arm should not rotate about the shaft protruding from the engine.
If governor seems to be in order, and engine cannot maintain RPM that it needs to (hunts), look towards the carburetor being fouled (clean out best you can, but don't soak since it is an EPA carburetor), air cleaner dirty (replace even if looks good), or loss of compression (check with compression tester, should be around 90 psi or better with engine warm).
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Check your governor and linkage for build up of dirt and grime. You should be able to move the governor by hand, with some resistance from the springs. The governor arm should not rotate about the shaft protruding from the engine.
If governor seems to be in order, and engine cannot maintain RPM that it needs to (hunts), look towards the carburetor being fouled (clean out best you can, but don't soak since it is an EPA carburetor), air cleaner dirty (replace even if looks good), or loss of compression (check with compression tester, should be around 90 psi or better with engine warm).