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Discussion Starter #1
I think my valve seals are bad. Here is why...

When driving on the high way at normal speed, RPMs ~3K-4K, if i let off the gas and let the engine stay in vac ~-28psi, and press the gas again i get large plume of smoke for 1-2secs, then its clear. High RPMs...no smoke.

The car WAS boosted, but its not NA. I was having the same problems, but it was MUCH worse with the turbo, turned out to be a bad turbo seal and it filled me exhaust with oil. But now its back but not nearly as bad.

Can I change the valve seals my self at home?
 

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4,227 Posts
After you take off the cam shafts you can see the seals. The problem is getting them out; I went to AutoZone and the only tool they had was too big. Looking on eBay you can't tell if whatever you're buying will be too big.
So I was screwed.
 

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you need the tools to compress the valve springs then clean the seats of the valves to make sure you get a proper seal then put it all back together it is do able you just need the proper tools or else....
 

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its your rings. valve seals will be when you first start your car in the morning it will be blue smoke because oil had the chance to seep down the valve and into the combustion chamber. once the car warms up the valve stem will expand a little and make a better seal no more leaky.
 

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Easy to do with the head off the car. Disassembling the head is easy, reassembly is a little tedious, but fairly straight forward.

The seals themselves "snap" on. I used a deep 10mm socket to seat them when I was reassembling a ported head.

If you're going that far, you might as well have new guides pressed in, replace the HG, head bolts replaced, clean the valves, have the springs tested for accuracy (rates), have the head tanked and lightly resurfaced.

There are also tools for doing the seals without removing the head, like running pressurized air into the combustion chamber to keep the valves from dropping out, specialized valve spring compressor for use with the head still on teh car, etc.
 

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its your rings. valve seals will be when you first start your car in the morning it will be blue smoke because oil had the chance to seep down the valve and into the combustion chamber. once the car warms up the valve stem will expand a little and make a better seal no more leaky.
the seals are rubber or synthetic and while they do shrink when warm, the vacuum condition the OP describes is typically valve stem seals or valve guides.

Bad rings blow by under compression, not vacuum.

really, a leak down test is the best way to narrow the issue, OP.
 

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I can haz custom title!
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Discussion Starter #10
Its *now* N/A. Type-O...sorry.

Thanks KFJ, A genius as always. I know its not the rings, it never smoked under boost. Just after the engine was in vac when the throttle was pressed it smoked, so I assume guides or seals were bad. I think I'll be pulling the head. Thanks everyone.
 
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