OK, here's the deal. Last year I built a motor for my camaro, and since day 1 it has smoked ever so slightly. Upon initial inspection, I found perfect compression in every cylinder. I ALSO discovered a valve seal on my #2 cylinder was sitting way up the stem. I fixed it, yet the motor still smoked.
Now, with finals over, I had time to yank the motor to take a closer look. I was expecting a ring problem. But what I found instead was a valve seal problem. Ok, 4 out of 8 of my exhaust valve seals are up the valve stems, and peeking through the spring, I can see that they are pretty much mangled. They are the posi-lock style, and on some the metal ring has been torn off, and some of the seals are torn. What is even more interesting is that the one seal on the intake side, on #2, the one I fixed previously, was BACK up the stem. I was not the one who assembled the heads, my machinist did them. Initially I assumed that he'd simply missed pushing down one of the seals. But I find it hard to believe that he missed 5 of them, and that still wouldnt explain how the one I fixed popped back up.
It has been suggested to me that the cam has too much lift, and that the keepers are grabbing at the seals and pulling them up. The lift on my cam is .533/.544, which would explain how there are more exhaust seals pulled up than intake seals. The thing is, the guy I got the heads from claimed to have run nearly .600 lift on them. He seemed like a good guy, and I'm inclined to believe him. Now. Before I put the motor together, I had my machinist take a look at the heads. He insisted on doing a valve job on the heads, even thought there were only 13K on the valves.
So my question here is, who is at fault? Did the guy I bought the heads from lie about the lift, or is it possible that my machinist somehow screwed them up when he did the valve job?
And how do I go about fixing the problem? Will machining the guides down solve the problem? Am I even correct in assuming that the lift on the cam is what is causing the seals to pop up?

 

That's a toughie. Here are my thoughts: Insufficient retainer to seal clearance would crush your seals and hit your guides but if you have less lift on your cam than the previous owner did and the heads were fine on his engine then you're ok too. Also, there really isn't anything on the retainers or valve locks to hook the seal with.

The posi-lock seals require a good bit of force to pull off the guides so I think maybe the inside of your springs are too close to the guides and since you had problems with the exhaust side, which has more lift than intake, that your springs are deforming more because they're being compressed more and so they grab the seal and pull up on it. From the factory, my L98 came with posi seals on the intake stems and umbrella seals on exhaust, maybe you should try going that route. The umbrella seals are designed to ride up and down on the stems. Good luck

Whatever happened with your problem with the lady at the BMV?

 

Were the guides machined lower to accept the positive seals?

Are you running the same valves as the original owner? (We used to use a lot of Buick and Ford Cleveland valves to prevent clearance problems because they are longer.) With longer valves you could run almost any lift until you slammed the piston tops without getting guide clearance problems, and maybe that's what the first owner of the heads did.

Are you using 7° or 10° retainers and locks?

 

I don't have much experance with valve seals but isn't there many sizes of positive seals? Is there a possibality that your machinest could have given you ther wrong seals and that is why they are lifting up?

 

How much clearance is there from the inner part of your valve springs to the seals? Also, check the outer diameter of the guides, make sure that you get the right size seals; if the guides been machined, they could be either .500" or .530", and the .530" seals are more common; so if they've been cut to .500" you may just have the wrong seals.

 

The guy I bought the heads from said the guides were cut down and tapered, although I'm not sure what that means for the seals. I dont currently have a spring compressor, so I cant check the clearance between the spring and the seals. All I've done is peeked through the coils to see the seals all torn up. And picked out the mangled chunks of metal rings that were collected in a pile on one of the head bolts. Gawd only knows how many more there are down in the oil pan. I'm using the same valves the previous owner had, Manley RaceFlos. Although my machinist did recut them. As for the keepers, 7º or 10º, I'm honestly not sure which they are.
Whatever is wrong, I'm fairly certain it's something my machinist screwed up. Because he has screwed up numerous other things on the motor. He sold me a mismatched set of rocker arms (7 self aligning and 9 nsa) an opened package of 28 hardened washers for the head bolts (most of us have 34 head bolts), nearly sold me the wrong pushrods, till I poined it out to him (roller cam), and when I went to pick up my parts from him, I couldnt help but notice that of all the crankshafts in his shop, mine was the only one laying on it's side.
From the way the seals look, it does appear that they are getting snaggled up in the springs. The metal rings have been mangled or thrown off, and some of the seals are torn or missing chunks along the sides.
So... you guys think my machinst just put the wrong seals on the heads?

As for the DMV incident: I drove the car down to the state capitol, where it passed inspection just fine, nothing wrong. The ticket: I'm still trying to fight my way out of that one; I'll probably end up paying double to keep it off my record.

~ Michelle :lala:

 

By any chance are you running double springs with dampners? if so your inside spring (not the dampner) might be wearing and pulling on the seals. When I had my new springs put on my machinest had to put different seals on to clear the id of the iner spring. Just a thought.

 

I think it's time to find a new machinest, that guy sounds like an idiot. I think you need new springs because I don't think you can get a smaller OD seal around the guides unless you machine the guides.

 

I'm rather currious why you went back to him after the first mistake....

Those aren't simple mistakes, or things that were accidently over looked. It sounds like they're habits of his and bad buisness, Thats a shady machinist and I wouldn't go back twice, let alone 4 times.