should I or shouldn't I?, flexible sealant on pushrod tube seals? Options

[iankarr]

Hi Guys,

I have new pushrod tubes and viton o-rings ready to install as my quest to keep kitty litter out of my garage continues...

The bores are super clean and look like they'd make a good seal...but when I serviced the tubes last year, they did leak a bit. That was using new viton, but the old tubes. The new tubes definitely seem to "seat" the rubber better.

What are your thoughts about using yamabond (or some other flexible sealant)? Is there any downside? I assume it would only go around the seals on the case side, right?

Thanks!

[Keith914]

Hmmm! I just finished carefully, no O ring damage, re-installing the existing tubes with a coating of engine oil, after very carefully cleaning their grooves of paint and flexible sealant ("snot") using new Viton O rings. All eight "popped" into place. After several short runs with engine up to operating temperature, perhaps 30 or so miles, three tubes appear to be leaking with thin oil trails along the bottom of the tubes. There is also oil on the underside of the lower tins just above these tubes.

The oil leaks have been reduced by at least a third, now about 4 to 5 drops after cool down, on the passenger side, and some oily surfaces, but no drops, on the driver side. I remain suspicious of the cylinder/case seals which may be the remaining leaks with oil dropping onto the tubes where it gravitates to the underside of these tubes. I am considering pulling the "leaking" tubes enough to put Yamabond on the O rings and reinserting them with the engine in place -- not easy, but quicker than pulling the engine again. If this does not fix the leaks, I will then have to address the only remaining possible leaks -- the cylinder/case seals -- which will require removing the drive train again (IMG:style_emoticons/default/dry.gif) Any comments?

[HAM Inc]

I only used oil. I've fixed drips from newly installed pushrod tubes by simply rotating them. I think the orings get bunched up during install on occasion and twisting unbunches them.

Smoothing the sharp edges at the case and head entries is important.

Hmmm! I just finished carefully, no O ring damage, re-installing the existing tubes with a coating of engine oil, after very carefully cleaning their grooves of paint and flexible sealant ("snot") using new Viton O rings. All eight "popped" into place. After several short runs with engine up to operating temperature, perhaps 30 or so miles, three tubes appear to be leaking with thin oil trails along the bottom of the tubes. There is also oil on the underside of the lower tins just above these tubes.

The oil leaks have been reduced by at least a third, now about 4 to 5 drops after cool down, on the passenger side, and some oily surfaces, but no drops, on the driver side. I remain suspicious of the cylinder/case seals which may be the remaining leaks with oil dropping onto the tubes where it gravitates to the underside of these tubes. I am considering pulling the "leaking" tubes enough to put Yamabond on the O rings and reinserting them with the engine in place -- not easy, but quicker than pulling the engine again. If this does not fix the leaks, I will then have to address the only remaining possible leaks -- the cylinder/case seals -- which will require removing the drive train again (IMG:style_emoticons/default/dry.gif) Any comments?