Do bad valve stem seals always look bad?
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From: Howard Beach, NYC
Car: 1990 TA
Engine: LB9 305
Transmission: 4L60
Do bad valve stem seals always look bad?
Did a search, but didn't find what I was looking for.
Puff (sometimes small, sometimes big) of blue smoke on startup. Figured it was valve stem seals. However, pulled the covers and all the seals looked o.k., none broken. Do bad valve seals always look bad, or can they be bad and look perfectly o.k.?
If not the seals, is there anything else that would give this puff? It is blue, not white or black. I have heard leaking injectors do the same, but I figured that would be more of a black smoke. And AFAIK rings give smoke all the time.
Puff (sometimes small, sometimes big) of blue smoke on startup. Figured it was valve stem seals. However, pulled the covers and all the seals looked o.k., none broken. Do bad valve seals always look bad, or can they be bad and look perfectly o.k.?
If not the seals, is there anything else that would give this puff? It is blue, not white or black. I have heard leaking injectors do the same, but I figured that would be more of a black smoke. And AFAIK rings give smoke all the time.
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From: Littleton, CO USA
Car: 82 Berlinetta/57 Bel Air
Engine: L92/LQ4 (both w/4" stroke)
Transmission: 4L80E/4L80E
Axle/Gears: 12B-3.73/9"-3.89
How did you see the seals just by pulling the valve covers?
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From: Valley of the Sun
Car: 82 Z28
Engine: Al LT1 headed LG4 305
Transmission: TH350
Axle/Gears: 3.73 posi with spacer
The stock type o-ring seals generally only last a couple of years. The get old brittle, crack, and just plain don't seal anything after a little age.
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From: Grand Rapids, MI
Car: Z28
Engine: Sb2.2 406
Transmission: Jerico 4 speed
Axle/Gears: Ford 9" 3.60
Originally posted by five7kid
How did you see the seals just by pulling the valve covers?
How did you see the seals just by pulling the valve covers?
But yep, factory valve seals get very leaky. It's the factorys "thing" to do.
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From: Howard Beach, NYC
Car: 1990 TA
Engine: LB9 305
Transmission: 4L60
I judge from the responses I was misinformed. No big, as this is the first time I've actually been in the engine.
I took it to a mechanic around here known for good work (I don't have the facilities to do it myself - no garage and a dirt driveway). He quoted $400 to do the work, but then pulled the cover and showed me. He said that if there was anything wrong pieces would be visible - otherwise they were good - and we didn't see any sign of even the smallest piece. Hey who am I to second guess - $400 you'd think he'd want to do the job.
I have the seals (I was going to do it before I decided not to take the chance), so I'll take it to someone and tell them just do it, don't second guess.
I took it to a mechanic around here known for good work (I don't have the facilities to do it myself - no garage and a dirt driveway). He quoted $400 to do the work, but then pulled the cover and showed me. He said that if there was anything wrong pieces would be visible - otherwise they were good - and we didn't see any sign of even the smallest piece. Hey who am I to second guess - $400 you'd think he'd want to do the job.
I have the seals (I was going to do it before I decided not to take the chance), so I'll take it to someone and tell them just do it, don't second guess.
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From: Grand Rapids, MI
Car: Z28
Engine: Sb2.2 406
Transmission: Jerico 4 speed
Axle/Gears: Ford 9" 3.60
Without REALLY peering under the springs, like getting your face 2" from the spring and staring with a trouble light, it really is hard to see the condition of the valve stem seals. So, if you didn't do that, then I'm not sure I would trust that mechanic (but that's just me).
As far as doing the work, you don't need any space really. I've changed valve seals on the street before. A few hand tools and a tool rental (valve spring compressor) and you're fine. And $400 is an awefully tall bill for what can be done in a few hours.
As far as doing the work, you don't need any space really. I've changed valve seals on the street before. A few hand tools and a tool rental (valve spring compressor) and you're fine. And $400 is an awefully tall bill for what can be done in a few hours.
Last edited by Stekman; Nov 4, 2004 at 11:42 AM.
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From: Howard Beach, NYC
Car: 1990 TA
Engine: LB9 305
Transmission: 4L60
Nah, its not the space I'm worried about. I do have plenty of that to work with. And I do own a valve spring compressor and the fitting for the spark plug hole to the compressor.
It's just, like I said I have a dirt driveway, and I really don't want to take the risk of dust/dirt flying right in there. Could kind of suck if I don't catch it.
It's just, like I said I have a dirt driveway, and I really don't want to take the risk of dust/dirt flying right in there. Could kind of suck if I don't catch it.
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From: Valley of the Sun
Car: 82 Z28
Engine: Al LT1 headed LG4 305
Transmission: TH350
Axle/Gears: 3.73 posi with spacer
How are you going to get dirt in there, its not very likely even if you did it in 50 winds. I wouldn't even worry about it.
You can get a set of heads rebuit for $400, he sounds like a crook. What does he charge $150/hr.
You can get a set of heads rebuit for $400, he sounds like a crook. What does he charge $150/hr.
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From: Grand Rapids, MI
Car: Z28
Engine: Sb2.2 406
Transmission: Jerico 4 speed
Axle/Gears: Ford 9" 3.60
Originally posted by ME Leigh
How are you going to get dirt in there, its not very likely even if you did it in 50 winds. I wouldn't even worry about it.
You can get a set of heads rebuit for $400, he sounds like a crook. What does he charge $150/hr.
How are you going to get dirt in there, its not very likely even if you did it in 50 winds. I wouldn't even worry about it.
You can get a set of heads rebuit for $400, he sounds like a crook. What does he charge $150/hr.
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From: MN
Car: 2009 Pontiac G8 GXP
Engine: LS3
Transmission: 6L80E
Axle/Gears: 3.27
The seals installed can LOOK ok...but if they are rock hard and brittle...replace them as they aren't working.
I know that from replacing my valve stem seals...they looked fine, until I tried to pry them off...no wonder I was getting smoke
I know that from replacing my valve stem seals...they looked fine, until I tried to pry them off...no wonder I was getting smoke
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From: Howard Beach, NYC
Car: 1990 TA
Engine: LB9 305
Transmission: 4L60
How are you going to get dirt in there
I'll try the water thing before I do it and see how it works out. Thanks for that idea.
You can get a set of heads rebuit for $400, he sounds like a crook.
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From: So. Ohio
Car: 88 Camaro
Engine: L98 350
Transmission: 700r4
My 88 has the stem/guide seals and o-rings on the intake, and just o-rings on the exhaust. The o-rings get baked hard and stop sealing after so long. I got the Fel Pro set that has the stem/guide seals and rings for both ex. and intake. This is good job to put off, which I'm doing till spring I guess.
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