Heads ?, cutting valve seals on exhaust side

[ApullinV6]

Well I took my heads off to get valve stem seals put on the exhaust side. Blue smoke on start up every since I put a high volume oil pump kit on the car. My question is when cutting the exhaust side for seals, do you cut the diameter down on the boss like the intake side or do you machine the boss down to the same height as the intake side? :

Need help here? I've got the heads at a local machine shop and he wants to make sure he right before any cutting takes place. I definately want to make sure he's right.

Anybody got any pics??

 

[ApullinV6]

O.K., I did alittle research. Sounds like I shouldn't put any seals on the exhaust side because they have been known to hang the valve open and cause some damage, ???

Well, I originally put some seals on the intake side from John's Performance and the car smoked, seals looked fine though. Now I bought some seals from Poston which seam to fit alot looser, not sure if I want to go back with them even though I put them on my first GN and they didnt' smoke.

What are the best seals to put on the intake side to better my chances of the car not smoking at start up and what else do I need to check?

 

[corsair231]

I had a problem with mine smoking on start after a fresh rebuild. I removed the heads and had the exhaust cut for seals. It stopped the smoke and I haven't had any problems with them. I never heard of anyone having a problem with umbrella seals hanging a valve open. I have heard of not having enough clearance and the valve spring binding because of it. You have to have the outside diameter reduced to fit the seal plus you have to machine the height down to allow enough clearance for spring compression once you add the extra thickness of the seal to the top of the boss. I talked with a couple of shop owners before I did mine and they were all familiar with the operation.
Most of the vendors sell the improved seals in 12 packs so it must be a pretty common modification. If your machinist is not sure about the process then he may need to talk with some other shops or either you may want to take your heads somewhere else.
One other thing. When I had mine done I purchased the seals from Poston's as well. When I got my heads back the machinist gave them back to me and told me that they were the wrong seals. He put the correct seals on it which he claimed were a newer, better seal anyway.
Like I said I haven't had any problems with it since as far as smoking goes. Now oil leaks, that's another story .

 

[blown okie]

throw the umbrella seals in the trash, have the shop put k-line seals on it, or a quality viton seal( they look like mini. timing cover seals). we use these almost exclusivley on everything we do at the machine shop I work at,and also have them on the rebuilt motor in the '84, they work great. as far valves sticking or it still smoking with these type of seals, look to the valve guides, worn to much or not concentric any more, guide liners or new guides would be due, assuming the rings are arn't junk or the wall finish is wrong causing it to smoke. they will probably have to machine the heads to fit the seals. this should be no problem for them to do, if they're not familiar w/ how to do this then grab your heads and run like hell away from the shop, you don't want them working on them anyways.