Valve stem seal wear

[greaseball]

I get a puff of smoke on start up on my '85 Vette with just under 50K, and it seems to be the result of valve seals drying out (as explained by another forum). If I use 'high-mileage' oil, do you believe that it may solve this problem? If it does, what happens if I go back to what I am now using, which is Wal-Mart Synthetic? Or should I keep using it? This engine does not require Synthetic, so Wally Syn, should be better than normal dino, (that's my theory anyhow-now you could laugh). thanks

 

[Fordiesel69]

The rubber is no longer contacting the stem correctly. Simple replacement is the only solution. Your 85' should not be that hard.

 

[Truck&Cycle]

All you need is a valve spring compression tool and a means of keeping the valve from falling into the piston when the holding clips are removed.

I used a spark plug that I broke the end off of and drilled through to make a hole in it. I screwed the plug in and used a small compressor with a rubber hose over the plug to keep a positive pressure in the cylinder. This held the valve up against its seal.

The valve seals were easy to pop off and the new ones snapped in place and all went well until the power went out and the compressor lost pressure. I watched the valve slowly sink and was able to grab it with my oil saturated fingers and stop it from falling in.

I couldn't pull it back up and remained in a holding pattern for a few minutes while calling for my wife to get me a set of pliers. No response. Thankfully the power came back on.

What are the chances of that one. About the same as my oil sensor sending unit going bad on the first start up after an oil change and the idiot light staying on. That happened to me once too.

 

[Fordiesel69]

Quote:

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What are the chances of that one. About the same as my oil sensor sending unit going bad on the first start up after an oil change and the idiot light staying on. That happened to me once too.

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Same here, I helped my couisin put in a new crank, oil pump, and bearings in his mitsubishi 3.0L and the same thing happened, the sending unit was bad. Luckily we waited till the next day to try a real mechancial guage instead of taking it back apart for nothing.

 

[Aldaris]

Quote:

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The valve seals were easy to pop off and the new ones snapped in place and all went well until the power went out and the compressor lost pressure. I watched the valve slowly sink and was able to grab it with my oil saturated fingers and stop it from falling in.

I couldn't pull it back up and remained in a holding pattern for a few minutes while calling for my wife to get me a set of pliers. No response. Thankfully the power came back on.

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I would have angrily rattled off to the wife every swear word in the book plus a few new ones if that happened to me!

 

[moribundman]

Quote:

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I would have angrily rattled off to the wife every swear word in the book plus a few new ones if that happened to me!

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Maybe she would have given you a length of rope in return. To feed into the combustion chamber through the spark plug hole next time, I mean.

 

[steveh]

I had the same problem with my 89 firebird formula 350. I had them replaced 3 times under warranty. At 38,000 when I traded it in it was doing it again. Don' know if this was a common problem with this motor or not.

 

[buster]

I've read that engines that use a bit of oil are less likely to develop this problem. Could there be any truth to that?

 

[moribundman]

A kernel of truth.

 

[427Z06]

Quote:

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The valve seals were easy to pop off and the new ones snapped in place and all went well until the power went out and the compressor lost pressure. I watched the valve slowly sink and was able to grab it with my oil saturated fingers and stop it from falling in.

I couldn't pull it back up and remained in a holding pattern for a few minutes while calling for my wife to get me a set of pliers. No response. Thankfully the power came back on.

What are the chances of that one. About the same as my oil sensor sending unit going bad on the first start up after an oil change and the idiot light staying on. That happened to me once too.

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Sorry, but the mental image is just too funny. Don't tell us your wife's name is Wilma, or I'll wet my pants.

I imagine people start to move away from you when lightning storms approach your area.

 

[alreadygone]

Think if you check there are new silicon(or other wonder material)seals with much better life. braze a quck connect, as used on a common air tool to the gutted spark plug, then hook it to a large capacity air compressor tank so there is plenty of air reserve.

No known cure for hardened rubber other than replacement.

Bob