Wtf?
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From: Marysville CA - 2002
Wtf?
a month ago i bought my 85 - during this time maybe 3 or 4 times it blew a little blue smoke on startup - the worse was this week-in i made a 135 mile run to Reno for a motorcycle event - got there & parked the car Saturday AM - this morning when i went to the parking lot & fired her up for the first time she really blew the smoke? - whats up with this - if it was valve seals wouldn't it do it all the time after setting? - car only has 34,000 mile on it - thanks - t
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From: Marysville CA - 2002
Originally Posted by cuisinartvette
They have low miles on them, but they are still 20 years old. They get brittle and go bad.
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Joined: Sep 2003
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From: charlotte nc
What you have is classic old brittle valve seals. GM used nitrile rubber on those things and they get very brittle with heat and age and fail to seal the valve stem. As you drive, oil tends to puddle around the springs keepers, and valve stems . When you let it sit, The oil runs down the valve stems and burns when you start it up. For some reason it seems to do this more after a longer run. Also, intakes are worse than exhausts because of the intake vacuum.
I doubt with only 34k on the clock that your valve guides are excessively worn. The only fix for this is to replace the valve seals . I suggest "Viton" or "Teflon" seal material. Also , while you are in there , replace the rocker arms with roller tip rockers. I'm not talking about full roller rockers because they are not as durable for a daily driver. What I'm suggesting are just the roller tips. Those rockers graetly reduce the side loading on the valve guides and make them last a lot longer. There have been waaaay too many Chevy smallblocks rebuilt for excessive oil smoke because of the valve seal / guide wear issue.
The job is fairly easy but aggravating. Depending on your skill level, you will need to decide if you want to tackle it yourself.
I doubt with only 34k on the clock that your valve guides are excessively worn. The only fix for this is to replace the valve seals . I suggest "Viton" or "Teflon" seal material. Also , while you are in there , replace the rocker arms with roller tip rockers. I'm not talking about full roller rockers because they are not as durable for a daily driver. What I'm suggesting are just the roller tips. Those rockers graetly reduce the side loading on the valve guides and make them last a lot longer. There have been waaaay too many Chevy smallblocks rebuilt for excessive oil smoke because of the valve seal / guide wear issue.
The job is fairly easy but aggravating. Depending on your skill level, you will need to decide if you want to tackle it yourself.
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From: Marysville CA - 2002
Originally Posted by dwestsr
What you have is classic old brittle valve seals. GM used nitrile rubber on those things and they get very brittle with heat and age and fail to seal the valve stem. As you drive, oil tends to puddle around the springs keepers, and valve stems . When you let it sit, The oil runs down the valve stems and burns when you start it up. For some reason it seems to do this more after a longer run. Also, intakes are worse than exhausts because of the intake vacuum.
I doubt with only 34k on the clock that your valve guides are excessively worn. The only fix for this is to replace the valve seals . I suggest "Viton" or "Teflon" seal material. Also , while you are in there , replace the rocker arms with roller tip rockers. I'm not talking about full roller rockers because they are not as durable for a daily driver. What I'm suggesting are just the roller tips. Those rockers graetly reduce the side loading on the valve guides and make them last a lot longer. There have been waaaay too many Chevy smallblocks rebuilt for excessive oil smoke because of the valve seal / guide wear issue.
The job is fairly easy but aggravating. Depending on your skill level, you will need to decide if you want to tackle it yourself.
I doubt with only 34k on the clock that your valve guides are excessively worn. The only fix for this is to replace the valve seals . I suggest "Viton" or "Teflon" seal material. Also , while you are in there , replace the rocker arms with roller tip rockers. I'm not talking about full roller rockers because they are not as durable for a daily driver. What I'm suggesting are just the roller tips. Those rockers graetly reduce the side loading on the valve guides and make them last a lot longer. There have been waaaay too many Chevy smallblocks rebuilt for excessive oil smoke because of the valve seal / guide wear issue.
The job is fairly easy but aggravating. Depending on your skill level, you will need to decide if you want to tackle it yourself.
Intermediate
Joined: Jul 2005
Posts: 43
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From: Greensboro North Carolina
A ounce of cure now is worth more than a pound of damage later. Replace those seals now. If you dont besides the embarrassment of blowing smoke from time to time, you eventually will foul out your plugs and maybe hurt your cats due to the oil consumption. the seals can be replaced without a major tear down using air pressure to keep the valves up when you replace the seals. Probably when you get on it good or let it back down it blows smoke too. 
Team Owner
Joined: Sep 2003
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From: Freedom is never more than one generation away from extinction.
St. Jude '03 thru '24
Originally Posted by 8T5
a month ago i bought my 85 - during this time maybe 3 or 4 times it blew a little blue smoke on startup - the worse was this week-in i made a 135 mile run to Reno for a motorcycle event - got there & parked the car Saturday AM - this morning when i went to the parking lot & fired her up for the first time she really blew the smoke? - whats up with this - if it was valve seals wouldn't it do it all the time after setting? - car only has 34,000 mile on it
Best bet is to replace the seals. Gonna cost about 50-60 bucks in parts and a day in the garage.
Good Luck
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Le Mans Master
Joined: Feb 1999
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From: levittown pa. usa Even a bad day with my `Vette, is better than a good day at work
St. Jude Donor '10
Originally Posted by FDAMFA
A ounce of cure now is worth more than a pound of damage later. Replace those seals now. If you dont besides the embarrassment of blowing smoke from time to time, you eventually will foul out your plugs and maybe hurt your cats due to the oil consumption. the seals can be replaced without a major tear down using air pressure to keep the valves up when you replace the seals. Probably when you get on it good or let it back down it blows smoke too.
-Been there ,done that. I used the "rope trick" ,since I did not have a long enough hose ( the story of my life 
) to reach the car. Worked great
Le Mans Master
Joined: Aug 2005
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From: Eagle River AK
St. Jude Donor '06-'07-'08-'09-'10,'14
Been there ,done that. I used the "rope trick" ,since I did not have a long enough hose ( the story of my life ) to reach the car. Worked great
Too bad about your short hose!
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Joined: Feb 2003
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From: Kingman AZ
Cruise-In VII Veteran
Cruise-In VIII
St. Jude Donor '06-'07-'08-'09-'10-'11-'12-'13-'14-'15-'16
Remove all of your spark plugs. Remove the valve covers. You take some poly rope that is a little smaller than the spark plug hole and heat up the end so it gets hard. Stick the end of the rope in the cylinder you want to work on and turn the motor over by hand (use a wrench on one of the top pulley bolts) until the rope is tight between the piston and the valve. This allows you to use a valve spring compressor without having the valve drop into your motor.
Le Mans Master
Joined: Aug 2005
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From: Eagle River AK
St. Jude Donor '06-'07-'08-'09-'10,'14
Remove all of your spark plugs. Remove the valve covers. You take some poly rope that is a little smaller than the spark plug hole and heat up the end so it gets hard. Stick the end of the rope in the cylinder you want to work on and turn the motor over by hand (use a wrench on one of the top pulley bolts) until the rope is tight between the piston and the valve. This allows you to use a valve spring compressor without having the valve drop into your motor.
I'll tackle it when the snow flies. I just changed the valve cover gaskets a month ago. Wish I had noticed the smoke before changing them.
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From: Marysville CA - 2002
Originally Posted by kenv
-Been there ,done that. I used the "rope trick" ,since I did not have a long enough hose ( the story of my life ) to reach the car. Worked great
