[6pack] Looking for advice on a washed out cylinder

[Robert M. Lang]

On Mon, 16 Nov 2009, Andrew Packard wrote:

> Hi list.  Please check out two photos I posted on the Forums, under Mechanical
> Repair, called "#4 cylinder wash-out".  I'm hoping to get advice through
> Forums or our traditional list format.  thanks in advance.

I'm not sure I've posted on 6-pack yet and if so cannot recall my access 
info, but there's two keys to this mystery:

1. down compression in cylinder 4

2. oil leaks.

My guess is a broken ring (probably the top compression ring) OR an 
improperly installed ring. The latter is actually more likely as it's a 
common installation problem. In some cases, even though you orient the 
rings the right way, when you compress them the gaps may line up and you 
get a lot of leakdown. That pressurizes the crankcase and stuff leaks 
EVERYWHERE.

I've seen this several times. Both with motors I built and others' motors 
that I've looked at for folks.

Seeing that you have the head off, drop the pan and pull the piston. 
You're already 90% there when the head is pulled.

I'll bet the spark plug was oil fouled too.

> Andy
> CD6746L

regards,
rml
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