Oil fouled plugs 7 & 8
05-26-2007, 08:10 AM
#1
Burning Brakes
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Location: Hudson Falls, N.Y. 76 Vette Modified L-48
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Oil fouled plugs 7 & 8
I've been searching the archives for this problem, and although some have had similar problems, none are quite the same....
When I changed the plugs last summer, the 7,8 plugs were carbon and oil soaked....the rest seemed fine, light brown insulator and clean....
I'm gonna pull 7, 8 today and see what I have now, but as a prerequisate, has anybody seen this...I can understand 1 bad plug, but both rear plugs? Hmmmmm.....
I also wonder if the dual quads might be helping the problem, but that is only conjecture on my part...
Additionally, if I install r46ts plugs in the 2 back cylinders, "might" that help resolve the issue??
When I changed the plugs last summer, the 7,8 plugs were carbon and oil soaked....the rest seemed fine, light brown insulator and clean....
I'm gonna pull 7, 8 today and see what I have now, but as a prerequisate, has anybody seen this...I can understand 1 bad plug, but both rear plugs? Hmmmmm.....
I also wonder if the dual quads might be helping the problem, but that is only conjecture on my part...Additionally, if I install r46ts plugs in the 2 back cylinders, "might" that help resolve the issue??
05-26-2007, 08:30 AM
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If you are sure it's oil and not gas you likely have a ring problem with those 2 cylinders. Only way to know for sure is to do a leakdown and compression test. A hotter plug may minimize the fouling but not correct the underlying problem. How does it run? Is it misfiring or burning oil?
05-26-2007, 08:46 AM
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Racer
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does it smoke when first stated up?
then clear after running a bit?
if so it could be guides and seals on your valves.
otherwise rings would be the best guess.
then clear after running a bit?
if so it could be guides and seals on your valves.
otherwise rings would be the best guess.
05-27-2007, 03:52 AM
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Burning Brakes
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Thanks for all your help and suggestions....as I've found in many parts of this car as I went thru it, the previous owner(s?) was a slug when it came to basic car maintainence (just gas it and drive it)...for all I know, the plugs I pulled the first time MIGHT have been installed at the factory, 100k ago 
Pulling the 2 suspect plugs yesterday, I found a very, very little carbon, and generally speaking they were fine, so I guess this was a false alarm post...sorry...but thanks again for chiming in
Pulling the 2 suspect plugs yesterday, I found a very, very little carbon, and generally speaking they were fine, so I guess this was a false alarm post...sorry...but thanks again for chiming in
05-27-2007, 07:49 AM
#8
Pro
Well, helpful for me as I have the same problem and had been following the thread. Now I know what to do...if the car ever gets here. It's been on a truck coming from Vegas....Jeez, he must be driving on the back roads! Every day is torture!
