I am referring to the camshaft inside the engine, didn't know there was more than one on this engine. The starter tested fine. Rechecked the gap on the valves today and there were correct, but I did not notice any slight movement in either valve when I turned the motor by hand. This I understand is the compression release on the camshaft to allow the pressure inside the cylinder to be released so the starter can spin the engine fast enough to start. If this is not correct someone please let me know. At any rate I am taking it to the repair shop tomorrow to let them find the problem, don't have the spare time to piddle on this anymore. Hopefully I can get an answer.
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Engine spins very slow
- Thread starter DavidO
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Export threadIf everything has checked out, it sounds like your mechanic has determined that the compression release on the camshaft is very worn or broken. When you set the valves, did you do them on TDC or individually without determining TDC? It's best to set them after first finding TDC on the compression stroke and then you need to go 1/4" past that spot so that you "clear" the compression release mechanism on the camshaft. From B&S: The compression release system lifts either the exhaust or the intake valve slightly off its seat during the compression event (this is why the piston is positioned past top dead center to about 1/4" down from the top of the cylinder when adjusting valve clearances). This releases pressure and reduces the force required to pull the starter rope or load on the starter motor.That isn't etched in stone however it could be the issue. Not etched in stone meaning most folks don't do it that way yet they don't suffer the consequences. I'm assuming through all this you have confirmed there is zero gas going into the oil. This can easily increase the compression and display those symptoms.
SeniorCitizen
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I am referring to the camshaft inside the engine, didn't know there was more than one on this engine. The starter tested fine. Rechecked the gap on the valves today and there were correct, but I did not notice any slight movement in either valve when I turned the motor by hand. This I understand is the compression release on the camshaft to allow the pressure inside the cylinder to be released so the starter can spin the engine fast enough to start. If this is not correct someone please let me know. At any rate I am taking it to the repair shop tomorrow to let them find the problem, don't have the spare time to piddle on this anymore. Hopefully I can get an answer.
To determine if the compression release is working, put your 0.001" or 0.002" feeler gauge between the valve stem and rocker lever as you rotate by hand to TDC on compression stroke. Keep moving the gauge a little as TDC is approached. If the release is functional you will feel the gauge tighten between valve stem end and rocker lever as the cam bump momentarily opens the valve.
Whether the exhaust or intake valve is designed to release compression that will need to be determined by engine numbers and the manufacturer or by the above test if the release is working as designed..