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Discussion Starter #1
Hi,
I'm burning some oil and getting some smoke from the right pipe, so I pulled the valve cover to take a look. At least two of the valve seals are sliding freely on the valve stems. The engine (stock A code) was rebuilt about nine years ago and the car driven very rarely before I bought it last year. My question is this, did they come loose just from age and drying out? Or could it be a more serious problem related to the guides?
Thanks for any input.

Paul
 

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The stock umbrella-type valve seals will slide up and down on the valve stem. When you say they are "sliding freely" do you mean that they are actually loose on the stem? If you slide them up the stem do they stay put, or are they so loose they fall back down? Is the rubber still soft and pliable or has it gotten hard? Just a couple things to consider. When do you see the smoke out the pipe? Immediately after start-up and then clearing up indicates leakage past the valves (seals and/or guides), smoking during acceleration indicates a cylinder sealing problem (rings, cylinder walls) Hope this helps... ::
 

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Thanks Roger, I did some research and since they have metal rings around them, I believe that they are the positive seal type (were?). I poked at one of them with a pick and it does not seem very soft. I was also able to slide it back down over the guide tip through the spring with the pick. Would they come loose like that just from getting old, or do you think there is also a guide problem?
Thanks,
Paul.
 
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I have white colored seals with a silver metal band around where they fit over the valve guide. I believe they are made of teflon, pretty hard material compared to the stock black rubber ones.

And yes, I had just replaced them because the car was smoking at idle. The new seals stopped the smoking immediately.

When I installed them they were a snug fit sliding down over the valve stem. When they seated all the way down around the valve guide, the fit between the seal and guide was very tight. I'm guessing I would have to pry them off the guide, that's how tight they are.
 

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Hi Paul...yep, what you describe sounds like an aftermarket seal sometimes called "Perfect Circle"-type seals. They should stay put on the guide and be a snug fit on the valve stem. I've seen these made of different materials, sometimes teflon (which is hard), sometimes a softer black rubber. Either something has happened to the seal itself, or to the top of the guide. Normally the top of the guide has to be machined to accept this type of seal and if done improperly could cause the seal to fit too loosly on the guide. Sounds like a deeper inspection may be in order to determine the true problem.
 
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