#3 cylinder oil fouling
 

Number 3 was oil fouling very badly to the point of misfiring. I pulled the head and pan; and removed the piston. The oil ring had been installed with the upper ring in proper placement, then the expander, but no lower ring. I removed the center expander and found the lower ring installed inside of it. Put it back together properly and reinstalled the piston in the bore. Now my question is...was this the sole source of my oil problem or was it also coming from the intake guide. #3 doesn't seem to have any more clearance than the others; but did have an oil deposit around it and all around the spark plug on the head. Was this deposit from the valve or from the swirl created by the combustion process and the improper oil ring installation? Any input would be appreciated...Greg

Re: #3 cylinder oil fouling
 

I doubt the oil is coming past the intake guide, that's usually not a problem on flatheads, on over head valves its common, the rings are the problem of oil getting into the cylinder on flatheads

Re: #3 cylinder oil fouling
 

Hi Greg,

If all piston ring gaps are aligned with each other, there will be a clear path for oil to travel upwards from the oil pan with no part of the metal rings scraping the oil off of the cylinder wall.

It is almost like having an air conditioned house with a window fan blowing all of the cool air outside.

Always stagger ring gaps.

Re: #3 cylinder oil fouling
 

Didn't pay attention to ring placement when it came out but they are correct now. Did the other three just to be sure. Thanks.