White smoke and higher speed when warm Briggs & Stratton
So I purchased a second hand lawn mower with a B&S 10T802 engine.
The previous owner already informed me that the lawn mower had been severely overfilled with oil once and ran for a while. It was drained for oil and cleaned up by a service shop, but next season it did not run anymore.
I got it running when I got it by cleaning the carburettor and everything seemed nice, but after 5-10 minutes it starts emitting white smoke from the exhaust and it runs at a much higher speed than when cool.
I understand white smoke means oil burning, so I`ve checked the crankcase breather valve and tube.
So my next thought is the piston rings or head gasket, but why would these break due to overfilling?
Also I cannot understand why broken head gasket will cause white smoke.
It does not seem to lack any power and it starts at first pull after primed.
Any help would be much appreciated.
Is this a good question?
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3 Comments
@mrlaurel how long did you run it? Any change in exhaust color? what did the plug face look like? Grey, brown, black etc?
by oldturkey03
When it is cool there are no visible smoke, only a strong smell which hurts a bit in th nose. When warm it is only white smoke, and still the smell.
There are visible oil around the exhaust so I'm quite sure it is oil burning.
Spark plug is black and oily wet with some debris/buildup. I've cleaned it and also replaced it, but the oily wet returns after a few minutes.
Btw, oil has been changed and gasoline is new.
by Kenneth
No one that can help me with this one? Winter is coming and I wanted an off season repair project.
by Kenneth