Zero compression on one cylinder

Bubba Peyregne

Forum Newbie
I have a 22hp Briggs and Stratton that quit running and I found that one cylinder has 0 yep zero compresssion. what would cause that and also I lost all of the oil in it except for 4oz. where did it go?
 
Hello Bubba,

Welcome to the forum.

First: Product ID label of the machine you are working on.
Second: The engine Model, Type and Serial numbers that are stamped into one of the valve/rocker covers.

Wild guesses

No compression in one cylinder typically means a bent or dropped push rod due to excessive valve lash.

Here are some possibilities that come to mind:

1. The oil was never checked since new.
2. The "plastic quick oil drain" has come open from vibration.
3. The lower crank seal
I have a 22hp Briggs and Stratton that quit running and I found that one cylinder has 0 yep zero compresssion. what would cause that and also I lost all of the oil in it except for 4oz. where did it go?
 
hole in piston would be my guess. Probably overheated and melted the crown. The gases push the oil out is usually what happens. A bad valve won't usually push all the oil out. Unless you are good mechanically enough to build an engine, or have someone you trust to do that, might just figure on replacing it with a new one. Occasionally you luck out and it is just a badly blown head gasket and you need a new head and gasket. That too usually comes from overheating.
 
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