Originally Posted by
Crash one
Also there are only two ways that oil can get into the cylinder. Past the rings or down through the valve guides.
If you are getting good compression then it can only be the valve guides.
Fitting a new cylinder/piston/ring set should solve the problem but is a bit of an overkill.
A new set of valve guides, and perhaps new valves would, in my opinion, fix it.
Just my two pennorth.
Crash, I too think replacing the cylinder/piston/ring kit is overkill, and I also suspect "ring chatter" is another misdiagnosis and have thought the valves were the source of the oil pass thru. However I'm at the end of my tether with this and as it's the insurance that's picking up 100% of the cost and I'm sick to death of being told it's problem X then when that is proven wrong its problem Y then that is also wrong etc, etc, I have put the insurance and engine shop ( a highly reputable outfit) on notice that this is the final attempt at a fix that I am going to allow and if it does not rectify the problem I want a brand new engine, not an overhauled or factory remanufactured one but completely new firewall forward setup and I don't give a flying f$&k if they come back again with another theory of what's causing the problem it's either a brand new set up or it's the lawyers. This aircraft should have been back in Scotland last summer but this issue has delayed its shipping. I truly wish I'd never bothered reporting the incident or making a claim and just bought a replacement prop and stuck it on myself right there next to the taxiway the day after the incident, them unbuttoning the engine for inspection has caused endless problems.