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-   -   Valve stem seals for H2AD ? (https://vansairforce.net/community/showthread.php?t=69483)

rocketbob 12-05-2011 07:00 PM

I don't agree with clearances being the only culprit because one can chrome cylinders to new specs on bore diameter, have the correct end gap and piston to cylinder wall clearances and they'll still use oil. But a chrome cylinder obviously has a different finish with very shallow peaks and valleys.

LifeofReiley 12-05-2011 07:09 PM

Quote:

Originally Posted by airtractor8 (Post 602445)
Hi Charlie

I have flown about 40hrs since fitting them and can only see a small reduction in consumption. They certainly didn't fix the problem totally. I think the cylinders are probably near the outer limits as mentioned in one of the previous posts. I will probably run them a while longer and change them out with new cylinders if consumption increases.

By chance do you know if your cylinders are tappered or straight bored? Also, a broken oil ring will cause oil blow by havoc... :)

airtractor8 12-05-2011 07:26 PM

Quote:

Originally Posted by LifeofReiley (Post 603121)
By chance do you know if your cylinders are tappered or straight bored? Also, a broken oil ring will cause oil blow by havoc... :)

They are Lycoming nitrited tapered bore. I guess it could have one or more broken oil rings but given that the consumption hasn't changed much since the second set of new rings was fitted I would have to be unlucky I think. Murfy says its certainly a possibility though.

LifeofReiley 12-05-2011 07:29 PM

Quote:

Originally Posted by airtractor8 (Post 603127)
They are Lycoming nitrited tapered bore. I guess it could have one or more broken oil rings but given that the consumption hasn't changed much since the second set of new rings was fitted I would have to be unlucky I think. Murfy says its certainly a possibility though.

My good friend had only one broken oil ring a couple of months ago and it just brings back memories when I read thru this thread. Maybe not... :)

LifeofReiley 12-05-2011 08:18 PM

Quote:

Originally Posted by airtractor8 (Post 603127)
They are Lycoming nitrited tapered bore. I guess it could have one or more broken oil rings but given that the consumption hasn't changed much since the second set of new rings was fitted I would have to be unlucky I think. Murfy says its certainly a possibility though.

Do you have the part # of the rings that were installed?

airtractor8 12-05-2011 08:37 PM

Quote:

Originally Posted by LifeofReiley (Post 603138)
Do you have the part # of the rings that were installed?

The first set were ECI the second and current set are genuine Lycoming. I don't have the part numbers near me at the moment.

fixnflyguy 12-06-2011 05:35 AM

H2AD/oil
 
Graham,
I am running an H2AD in my -4. I built the engine up myself, and have reconditioned cylinders on it. I did the first 50hrs with same oil you used,running 75% or higher throttle settings, and now run the 100 plus also. I have about 100hrs on it now, and it is using about 1/2 qt every 8-10 hrs. Like yourself, I never fill above 5 qts. I have heard all the recomendations for the valve stem seals also, but didnt put them on mine. Sounds like you have done all the right things, so I will be curious if you find a solution! Good luck.

TangoT 03-18-2014 12:32 PM

How's the intake stems seals working?
 
Quote:

Originally Posted by mike in phx (Post 521381)
when i built my engine i have P10 new overhauled cylinders and 9.5-1 comp pistons total seal rings.
And when you use the rings it will puff smoke on idle.
Because of the added vacum, on intake stroke it pulls oil thru the guide.
So i added valve stem seals on exaust and intake valve. I have over 250
hours on valve stem seals and on the new turbo motor im using 1/4 quart oil on 35 hours.
If you need more info give me a call 602 697 4080

I'm wondering how this is working out? I have a Lyc IO-360-C1E6 that and considering doing the same. Any updates would be appreciated!


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