briggs 18.5 els 500/ no compression

[jackmack]

Could somebody please tell me which direction to go . How do you tellwhy you have no compression. Is it a blown head gasket ? Motor just spins freely.

 

[gregjo1948]

I'm assuming that this engine is a single cylinder. I think a blown head gasket will still show some comprssion and not let the engine spin freely. I would say it's probably a valve problem. I'd say the exhaust valve is stuck open from built up carbon on the stem or the valve guide has slid in towards the piston far enough to hold the valve open. With an open valve, you'll not have any compression and the engine will spin freely. Without more info that's my best guess. I've seen it 3 times in the last month. Check the compression. If you don't have tester, pull the spark plug and cover the hole with a thumb or finger. Spin the engine over and if your finger doesn't get push away, you have no comprssion. If that's the problem, let us know and we'll tell you how to proceed. gregjo1948

 

[Fish]

If it spins "freely", then it may be real bad. Take out the plug, and stick a pencil in the hole toward the center, and slowly rotate the top of the flywheel
by hand while pressing in on the pencil. If the pencil doesn't move, well...... Not too good, pull the head to get a better look.