So i recently changed the head gasket on my kohler ch740 because of a very minor oil burning issue. when taking out the head i loosened two of the top breather cover screws on accident trying to loosen the head. i changed everything and put everything back together including those two top screws but now when i start the engine, a massive amount of white smoke comes out the exhaust and oil leaking bad out of the top of the engine (i think where the breather cover is). both cylinders now get full of oil too after just 5 seconds of running the engine. what could’ve possible happened??
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Mower smoking and leaking oil after head gasket repair
NinjaSneak
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So i recently changed the head gasket on my kohler ch740 because of a very minor oil burning issue. when taking out the head i loosened two of the top breather cover screws on accident trying to loosen the head. i changed everything and put everything back together including those two top screws but now when i start the engine, a massive amount of white smoke comes out the exhaust and oil leaking bad out of the top of the engine (i think where the breather cover is). both cylinders now get full of oil too after just 5 seconds of running the engine. what could’ve possible happened??
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most likely not, before the head gasket change it was running very smooth with almost no problems except for the small oil leak somewhere which i thought was the head gasket.
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is there a process you recommend to check what is wrong? i know the rings are most likely good but how do i check if the valves or good or not? and im gonna redo the head gasket again with a new breather cover gasket as well.
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Yes, currently redoing it and putting a new breather cover gasket
Did the engine get tipped long enough for oil to seep past the rings? Is the oil at the correct level? My next step would be a cylinder leak down test to see what is going on. As dirty as the block looks, could have been overheated several times which is shorted engine life. Good luck.
That's some good cleanup work you did then.....
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If the oil is leaking out of the breather cover, it's most likely leaking into the breather chamber under the cover, filling with oil and carrying over thru the breather hose into the air cleaner. Remove and replace the breather cover gasket. But DO NOT get anything, dirt or gasket material, into the oil pressure feeds to the lifters under the cover. Anything that falls in there will be forced into the lifters and you'll be chasing lifter problems then.
Indeed.That's some good cleanup work you did then.....
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Jesus christ... I'd say there's a **** ton of trash in there 🤣
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redoing everything and will clean it up spotless 😔 should’ve cleaned it before but i was in a rush
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How many hours on the engine? You should have left the engine alone and kept running it. Was it hard to start, down on power? Kohler Command is a great engine. Next step is to take it to a shop for a diagnosis.
Why people insist they know shortcuts.
There arent any, and they know little about repairs.
I know little about weeds, grass and fungus.
You problem is the breather cover gasket.
Replace the switch also if equipped.
Full system pressure there.
About 50psi at startup dropping to about 25.
Clean every spec of gasket.
Or you be doing it again.
There arent any, and they know little about repairs.
I know little about weeds, grass and fungus.
You problem is the breather cover gasket.
Replace the switch also if equipped.
Full system pressure there.
About 50psi at startup dropping to about 25.
Clean every spec of gasket.
Or you be doing it again.
Troll
Joined
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2,360 Posts
If you say something on purpose to make a person angry, you're a troll. In this case you're trolling me.
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