Burnt valve
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bertsmobile1
Lawn Royalty
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That is not a burnt valve
It is oil burning on the surface
The oil is being forced up the valve stem usually because the crankcase pressure is too high.
High crankcase pressure is generally due to either a blown head gasket or a faulty breather.
Overheating around the exhaust port is usually caused from to little valve lash so the exhaust valve opens too early & closes too late.
It is oil burning on the surface
The oil is being forced up the valve stem usually because the crankcase pressure is too high.
High crankcase pressure is generally due to either a blown head gasket or a faulty breather.
Overheating around the exhaust port is usually caused from to little valve lash so the exhaust valve opens too early & closes too late.
no, the other exhaust is clean.
cpurvis
Lawn Addict
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If this engine is still under warranty (30 hours), I'd let the dealer take a look at it.
If not, I'd remove that head and look at it myself.
Mower King
Well-Known Member
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Like others have said, that is not a burnt valve. That is oil burning on the head because, that is the Exhaust valve and that is where all the heat is centered. This is a result of too much heat, causes can be many....debris build-up on the cooling fins of that cyl head, debris build-up on grass screen (air intake on top of eng for cooling), engine not being run a WOT or eng not turning enough rpm's...among other things, but, you have cleaned up the sealant area for the V cover to seal real good!
The only way to "SEE" a burnt valve is to remove a head and look at the valve were it mates the V seat!
The only way to "SEE" a burnt valve is to remove a head and look at the valve were it mates the V seat!
