Valve stem umbrella seals

[Powdermonkey]

Hi Folks- Running several listeroid clones.  Some twins, some single cylinder units.  The Indian varieties have a bit of clearance between the valve stem and head. 

I'm looking to see if folks have retrofitted an umbrella seal on any of these heads?  If you've done it, I'd be most grateful for pictures or machining concepts that would benefit the endeavor.

[cobbadog]

I remember those umbrella or cup seals being used on the early Holden Grey Motors. Over time they were made obsolete and replaced with a simple "O" ring which did the sob perfectly and there was no need to do any machining work as they self levelled out to where the valve would be when fully open. We use to just push the "O" ring almost to the bottom of the stem when the valve was fitted into the head with a lot of oil on the stem, set the clearances and start up and go.

[38ac]

There should be very little oil up there thus I'm not sure what problem seals will fix?  The problem I have seen is India saw fit to drill holes in the side some of the guides.  If so any oil in the wells just runs down the valve stems. If your guides are drilled plug the holes and the problem is solved.

[Powdermonkey]

There should be very little oil up there thus I'm not sure what problem seals will fix?  The problem I have seen is India saw fit to drill holes in the side some of the guides.  If so any oil in the wells just runs down the valve stems. If your guides are drilled plug the holes and the problem is solved.

38AC- Please advise.  I normally add 4-8 ounces of oil up top during every run session.  By the end of the day, the "reservoir" is basically empty.  Am I doing it wrong? 

[dieselgman]

Butch is right... there will be no advantage nor reason to use an umbrella type valve stem seal. That design is only valid for a fully enclosed valve cover environment with a large amount of suspended oil mist/splash. Your Lister requires a small amount of oil to lubricate the valve guides/valve stems and that is supplied via a tiny amount of splash off the valve springs drawing on the oil you manually place there in the valve spring reservoir every 8 hours of operation (or thereabouts). Also, avoid the drilled valve guide mod as Butch has also indicated.

Yes, it sounds like you are doing it right.

dieselgman