thebruce

I decided to pull my intake manifold and try to track down the blue smoke at startup and oil consumption problem. Here's what I saw:





There is oil sitting on the stem-side of the valves (which may or may not be apparent in the pictures).

The heads are new, so I don't think it's a valve guide issue. I'm assuming this is purely a valve stem seal issue, right? Trick Flow Specialties recommended the same seals that came on the heads new, but since they obviously didn't work AT ALL, I'm going to use some other kind. Should I be looking at umbrella seals or just higher quality regular seals?

Thanks.

:cheers:

Barry's70LT1

I use both on my heads. GM make an excellent seal that fits over the casting on the head (made to fit stock GM heads) and, as well, use the stock "O" ring.

I've been using this combination for about 12 - 15 years now and have had no problems at all.

Barry

Fevre

I experienced the same thing with my trick flows, I had to have some work done on them when I had a pistons explode and I think the company that did the work ordered the replacement seals. I have since ordered a set of crane seals to see if that cures the problem. Might be a while before I put the heads back together so can't give you any report on whether it cures it or not. BTW the guides seem to be tight but I am not an expert on it.

turtlevette

my L-98 heads blew smoke something awlfull when i put the stock O ring seals on. I got the fel pro heavy duty exhaust seals which were basically umbrella seals and not a hint of smoke anymore.

thebruce

This is probably something I'll pay someone to fix for me, but if I get the time, I may change the seals myself. Turtlevette, did you have to make any mods to your heads to put the seals on?

yellow 72

The seals on my TF heads had a habit of pulling off the guides. I replaced them with Crane pieces and have had no futher problems :cheers:

GasketDude

Which part number heads do you have? Might be able to find a seal part# to use for your heads. Do you have a micrometer or dial indicator should we need an exact measurement?

Also measure the O.D of valve springs, either 1.25" or 1.47". Measure I.D. of spring as a reference also. Valve stem O.D diameter should be 11/32" = .34375". May need to measure the the O.D of (the top of) valve guide and how far down it's machined for seal to fit on.

Last thought, do you know the specs of your cam? Too much lift and the Valve Retainer can contact the seal! This includes cam and rocker ratio into max lift value. So if your 1.25" springs can handle .520" lift, 1.47" = .540" and you add 1.6 ratio rockers, (depending on cam lift) you'll smash the seals! Need to do the math on this "stack up" for the whole assembly.

Check it out and repost.

turtlevette

NO, Most rebuild shops use them anyway. I used an attachment to an air compressor that goes in the sparkplug hole and a cheap valve spring compressor from autozone to do the job with the heads on the car.