Re: My B&S Intek 18.5 hp won’t turn over.
2023/05/03 19:56:13
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The camshaft issue is a common cause of this condition but not the only one. Check the valve adjustment first - it's easy, 5 minutes tops. Pull the spark plug and the valve cover. Turn the engine over by hand to top dead center on the compression stroke and then continue turning so the piston moves back down about a 1/4". You can check this using screw driver in the spark plug hole.
Now check the valve lash on the intake with a feeler gauge. You can find the spec for your engine by model and serial number but many are 0.003-0.005 for intake. There are many Youtube videos on this. Once the intake lash is set within spec turn the engine over by hand and watch the intake valve, just after it closes you should see it bump open a tiny bit. If you see the bump the compression release is working and likely not the issue.
If you see the intake valve bump you need to look elsewhere for the issue. It could be a something with the starter, either weak or gears binding. Some engines have a ground wire connected at one of the starter bolts. I had one last week where somebody had put that ground wire under the starter bracket. The starter would spin the engine without the plug in but with any compression the starter gear was off just enough to bind against the flywheel. I moved the ground to the outside of the bracket and fixed!