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dsraven · 02-23-2018, 10:22 AM

assuming your crankcase breather system is functioning properly and free flowing in all areas
-valve adjustment
-pull all the spark plugs and check their condition (oil soaked, dry, brown, black etc)
-cylinder leak down test
-compression test, dry
-compression test, wet

compression tests can be a bit misleading if the engine has an oil consumption problem because they can mimick a wet compression test, sort of sealing the rings with oil getting past the oil control rings. best do do the leak down test dry first while everything is still dry inside there like normal. then the dry comp test, then the wet (with oil squirted into the cylinder prior to compression test). the comp test is done with all spark plugs out, the throttle tied wide open and the coil power wire off. have an extra battery of some booster cables ready so the cranking speed stays the same for all the comp tests, otherwise the results are skewed. of course it is always best to start with a valve adjustment so you also don't get skewed results and each cylinder has it's best chance.

02-23-2018, 10:22 AM	#6
dsraven Registered User Join Date: Nov 2010 Location: calgary alberta Posts: 8,501	Re: Oil out of crankcase vent tube assuming your crankcase breather system is functioning properly and free flowing in all areas -valve adjustment -pull all the spark plugs and check their condition (oil soaked, dry, brown, black etc) -cylinder leak down test -compression test, dry -compression test, wet compression tests can be a bit misleading if the engine has an oil consumption problem because they can mimick a wet compression test, sort of sealing the rings with oil getting past the oil control rings. best do do the leak down test dry first while everything is still dry inside there like normal. then the dry comp test, then the wet (with oil squirted into the cylinder prior to compression test). the comp test is done with all spark plugs out, the throttle tied wide open and the coil power wire off. have an extra battery of some booster cables ready so the cranking speed stays the same for all the comp tests, otherwise the results are skewed. of course it is always best to start with a valve adjustment so you also don't get skewed results and each cylinder has it's best chance.