Now the spark plugs are fouling -- carb overhaul?

[67L48]

Started a new thread that better describes the symptom I'm now dealing with ...

Bad news.  Installed all the new parts and the car ran great.  Took a 5 mile drive and went back to the garage.  After sitting, the car had a hard time starting and emitted quite a bit of smoke on the restart.  So, the mechanic pulled the plugs and found that they were already starting to foul.  The thought is that carb is leaking fuel through the internals and that it needs a complete overhaul, as he's done all he can do to tune the carb.  They want $425 for the carb overhaul, P&L (beyond what I'm already into it for). 

Does this sound correct?  Thoughts?

[67L48]

I did some checking online and it seems to pass the sniff test.  People with fouling plugs apparently do go to the carb settings to eliminate fuel drip/leak -- when the settings fail, they rebuild.  I gave the green light to the shop.  Will have parts tomorrow AM and hopefully the odyssey will come to a conclusion.  It hurts, but at the same time, I'm really excited to get my car running great again.  For years it ran perfect.  But the past few years, it's been about 2/3 the car that I was used to.  Part of that was due to moving from sea level to 5,000 ft.  Part of it, I believe, was the crap I'm now dealing with.  Will post back when I have more info.

[crobjones2]

Depends on how the plugs are fouling. I am going to have to rebuild my engine due to an oil fouling I suspect is from the oil ring on the piston. When the heads came off, it was quite apparednt there was an issue in that cylinder. all but the bad one have a little bit of dry carbon build up, but the bad one the carbon was thick and moist
Hopefully you dont have the same issue

Which cylinder is fouling? - I lost #7

[rich69rs]

I also live at 4750 ft (Carson Valley in western Nevada).  Had the main jets in the 2Bbl carbs on both my '66 Chevelle and '69 RS rejetted for the difference in altidude.  Less oxygen up here, need to lean it out a little (smaller main jets) to maintain optimum air/fuel ratio.

[67L48]

OK.  Carb was rebuilt and is running great.  Apparently, the guy in the shop is the Charlie Daniels of the carb -- a wizard.  Picked up my car at 3:30 PM yesterday and man was it great to have it back.  Runs better than it has in 4 years.  One of the members here wrote me this in an email:

Quadrajet carburetors are subject to leakage/seepage around lead plugs found at the base of the jet wells.  These plugs are visible from the bottom of the carburetor.  When they’re over the hill and begin to leak, they allow gasoline to drain out of the bowl and into the intake manifold.  They will do it every time the car is shut off and that dumps at least 1/3 of a cup of raw gasoline that has to evaporate or be expelled from the cylinders upon restart.  Plus, before the car can run again, the bowl has to refill with gasoline, a process that requires spinning over the motor with the starter unless you have an electric fuel pump.  It sounds as if the lead plugs are doing a little more than seeping in your carburetor.  They are probably dripping rather than seeping.

I think this is spot-on as to what was happening.  The mech rebuilt the carb, tuned it, and voila, car runs great.  I'm happy.

[jdv69z]

Depends on how the plugs are fouling. I am going to have to rebuild my engine due to an oil fouling I suspect is from the oil ring on the piston. When the heads came off, it was quite apparednt there was an issue in that cylinder. all but the bad one have a little bit of dry carbon build up, but the bad one the carbon was thick and moist
Hopefully you dont have the same issue

Which cylinder is fouling? - I lost #7

Interesting, when I rebuilt my 302 approx 1993, it was also cylinder #7 which had ring failure/oil fouling. The idle was always erratic as well. Plugs do tell the story if you are willing to believe them.

Jimmy V.

Jimmy V.