high crank case pressure at dipstick, yet low pressure leaving from crankcase vent.

barrythecucumber

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  • / high crank case pressure at dipstick, yet low pressure leaving from crankcase vent.
kawasaki FH601V 20hp vertical shaft engine in a john deere gx335. 235 hours, year 2004. i just purchased and it has been sitting for a while i guess.
the crank case pressure is so high that oil droplets spray out when i remove dipstick during idle. i have removed crankcase valve, thinking it was plugged, cleaned it out, but still the pressure is high. when i check pressure at the vent hose returning crankcase valve pressure to the carb, it has very low pressure if any at all, yet the dipstick still has very high pressure. perhaps i have a head gasket leak? the oil blackened quickly after i changed it. note there are no signs of oil sweat on outside of engine. engine runs fine, maybe lacking a little power but i just purchased so it is hard to know for sure. i just think it is odd that the crankcase pressure is different at 2 different locations. maybe this is a symptom someone here can help diagnose. thanks.
 

txmowman

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  • / high crank case pressure at dipstick, yet low pressure leaving from crankcase vent.
What you are seeing is completely normal. There is a great deal of windage happening inside the crankcase. Why would you feel the need to remove a dipstick on a running engine in the first place? If you do this at high idle, you will see even more. Only remove the dipstick with the engine stopped to make sure the oil level is correct. Check the oil daily.
Or, wait for Bertsmobile's reply where you will get a lesson on how oil was made and that it was originated and perfected in Australia.
 

ILENGINE

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  • / high crank case pressure at dipstick, yet low pressure leaving from crankcase vent.
think of the engine crankcase with the one way breather system. Without an air inlet the crankcase expells all the air and then the breather maintains a slight vacuum in the crankcase. but removing the dipstick you open the system to atmospheric air and allow the free exchange of air through the dipstick and the pistons going up and down creates a very good air pump. Piston goes up and sucks air in through the dipstick tube. Piston goes down and expells that air out the dipstick tube along with the oil.
 
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