What's wrong?
Thread Starter
Intermediate
Joined: Aug 2006
Posts: 38
Likes: 0
From: Sugarland TX
What's wrong?
Out for early morning run in Houston in my '68, it's numbers matching 427 400 hp (engine rebuilt 5 years ago, 3k miles since). As entering the neighborhood after coming off the expressway I notice engine running a bit rough and some loss of power. Once in driveway I can see left side exhaust pattern rough and after a minute or so the left side starts throwing out a lot of white smoke (vs. blue that would contain oil). Right side exhaust is fine. So what has happened to one of the cylinders on the left side? Car will still start up ok, but left side smoking like a chimney. What happened??
Former Vendor
Joined: Aug 2006
Posts: 76,656
Likes: 1,847
From: Jeffersonville Indiana 812-288-7103
St. Jude Donor '08-'09-'10-'11-'12-'13-'14-'15
You might try to re-torque the intake gasket while you at it. White smoke is anti-freeze!
An old trick to confirm this is to take your finger and touch the inside edge of the pipe and then touch it to your tongue it should taste sweet (don't swallow).. if this is the case for sure it's anti-freeze.
An old trick to confirm this is to take your finger and touch the inside edge of the pipe and then touch it to your tongue it should taste sweet (don't swallow).. if this is the case for sure it's anti-freeze.
Pro
Joined: Jun 2009
Posts: 613
Likes: 3
From: Fleetwood PA
Yep....white smoke = no good.
Not that any smoke is good.
Hopefully just a head gasket, not cracked head or block. Check and see if your radiator is low, and check your dipstick for milky colored oil.
Good luck with it, and keep us up to date on what you find.
Not that any smoke is good.
Hopefully just a head gasket, not cracked head or block. Check and see if your radiator is low, and check your dipstick for milky colored oil.
Good luck with it, and keep us up to date on what you find.
Race Director
Joined: Jan 2000
Posts: 13,011
Likes: 2,249
From: Corsicana, Tx
2020 C2 of the Year - Modified Winner
2020 Corvette of the Year (performance mods)
C2 of Year Winner (performance mods) 2019
2017 C2 of Year Finalist
Pull the plugs. The one with water in it will definitely look different.
Be VERY careful about starting it after it has sat for a bit. If the cylinder fills up with water and you hit the key..there IS enough power in the starter to bend/break a rod, crack a block etc when the piston *hydraulic's* as it rises. More than one good motor has been killed this way. Pull the plugs..you'll see the issue.
JIM
Be VERY careful about starting it after it has sat for a bit. If the cylinder fills up with water and you hit the key..there IS enough power in the starter to bend/break a rod, crack a block etc when the piston *hydraulic's* as it rises. More than one good motor has been killed this way. Pull the plugs..you'll see the issue.
JIM
Pro
Joined: Dec 2004
Posts: 710
Likes: 2
From: Raynham MA
What ended up being the issue here? I just noticed a small amount of white smoke coming from the pass side exhaust manifold. Just for a couple minutes and not a lot. But it happened.
Trying to figure out what it is.
Thanks
Trying to figure out what it is.
Thanks
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Pro
Joined: Dec 2004
Posts: 710
Likes: 2
From: Raynham MA
Cool, thanks. Ya, it was probably about a minute. I also noticed my valvue covers bolts were a little loose and there is a little oil residue down there. Doesnt look like it hit the exhaust manifold but maybe it did. I tightened the bolts and cleaned it up with simple green and paper towels. I'll keep an eye on it.
