Hi guys,

After learning a lot from rebuilding my 272, I am in need of some more forum advice... please of course!!

I have ran the engine for a total of about 60mins since rebuild. I pulled the plugs and am finding a wet thin layer of oil on top of the pistons. Is this normal?

My thoughts are-

1) Rings are still seating?
2) my pcv valve is sucking oil due to a poorly designed baffle (my bad) and I suspect it's accumulating on top of the pistons and plugs are dry.

There is no smoke from the headers while running.

Under normal operating conditions, what should the top of a piston look/feel like once the plug has been pulled.







Thanks, Dennis.

56 F100 - 272 Y Block
NSW, Australia.

You mention sixty minutes of running but no mention if this is simply stationary or being driven.  Are all pistons oily or just a selected few?  If this is stationary running, then there’s a good chance that the rings are not seated.  By driving or putting the engine on an engine dyno, the rings can be heated sufficiently through loading and temperature variation to actually seat the rings.  Be forewarned that an excess of stationary or no load running on a freshly built engine can glaze the cylinder walls thus making the rings that much harder to seat once the engine is actually being driven.

Lorena, Texas (South of Waco)

Thanks Ted!

Ok, yeah the engine is still on the stand and will not be in the truck for quite a while- I have been trying to tune it. Thanks for the info about running it unloaded- I'd better stop starting it up to get my kicks on the weekends.

All piston tops are oily. So it seems that the rings need a driving load to seat. I'll wait till then and I'll check the tops of the pistons after 500-1000km.

Thanks for the advice, always appreciated!


Thanks, Dennis.

56 F100 - 272 Y Block
NSW, Australia.