Oily Lower Plugs O-360

[carusoam]

Other things to consider...

1) Climb angle gets reduced when climbing at 120mias.  A common temp control vs. climb speed compromise.

2) take pictures of the surface of the cylinder walls.  When they get honed, The have a diamond shaped pattern scratched in them.  If they have a worn surface there won't be a pattern in some places.  Lots of cameras around lately.

PP ideas only...

Best regards,

-a-

Edited February 24, 2017 by carusoam

[Piloto]

• When oil drips out of the plugs it is time for overhaul or new cylinders.

[N201MKTurbo]

Last time I checked a set of rings was about $100. I have pulled cylinders, cleaned the piston, ran a hone down the barrel sized and installed new rings. All it costs me is the price of the rings and a few dollars in gaskets along with a few hours of my life.

If you are going to do one you might as well do them all. By the time you have enough parts off to get one off, you are more than half way to getting them all off.

Don't discount the piston. If the lands are tapered, get a new piston or you will be just throwing good money after bad. Besides what is going to wear more? Hard piston rings or a soft piston?

If you are paying someone to do it figure $500/cyl for a piston, rings and cylinder labor + 10 hours to R&R them. So stop the oil for 3 AMUs

Or buy an extra case of oil a year until TBO for $75/yr....

[Drumstick]

Logbook makes no mention of cylinders being new or otherwise.  Sticker in book from Lyc/Textron says "overhauled/rebuilt in accordance with the applicable Textron Lycoming manuals".

[geoffb]

I feel reasonably confident saying that If it came from Lycoming in this century, it got new nickel cylinders.  I'd bet it's valve guide leakage.  My #4 does that same.  Good compression, runs fine.  These engines do not have valve seals so it doesn't take much to get a little oil down the stems while it's sitting.