Hello Dear C-Friends,
I would be most grateful for your experience & expertise on the subject of reading plugs.
Please see attached pics of my plugs. You'll see that the ceramic center and electrode-strap all seem to have a good light brown color.. not too rich nor too lean. However, there are two #5 & #7(there are multiple pics of the same ones)which have what looks like oil on the plug threads only.. (maybe unburned fuel?). Also, two or three plugs are darker brown on one side, the side of the gap, is that normal? I pulled these plugs from a cold engine, after several days sitting, so wouldn't any fuel evaporate by then? I've read that unburned fuel on plugs looks black, and oil fouling is a rust color...? A combination of both? I've ruled out valve cover oil leaks. Suspect maybe valve seals..
despite its 15k original miles, the car is 50 years old.
The fact that fluid is only on the threads has me stumped. The plugs are not fouled. Air/fuel ratio is good. Timing is good. Air cleaner is new. These plugs have about 900 recent miles in them. The car does not blow out smoke(blue or white) upon cold start.. sometimes a small amount of steam from water evaporation as it comes up to temp.
I do seem to be losing some oil lately, which is new. I've only driven the car a total of about 1,000 miles since getting her.
The only thing I can think of is either a couple of bad valve seals, or fuel leaking down from carb. Maybe something totally benign. Thoughts?
Thanks for taking a look.
Alex
I would be most grateful for your experience & expertise on the subject of reading plugs.
Please see attached pics of my plugs. You'll see that the ceramic center and electrode-strap all seem to have a good light brown color.. not too rich nor too lean. However, there are two #5 & #7(there are multiple pics of the same ones)which have what looks like oil on the plug threads only.. (maybe unburned fuel?). Also, two or three plugs are darker brown on one side, the side of the gap, is that normal? I pulled these plugs from a cold engine, after several days sitting, so wouldn't any fuel evaporate by then? I've read that unburned fuel on plugs looks black, and oil fouling is a rust color...? A combination of both? I've ruled out valve cover oil leaks. Suspect maybe valve seals..
despite its 15k original miles, the car is 50 years old.
The fact that fluid is only on the threads has me stumped. The plugs are not fouled. Air/fuel ratio is good. Timing is good. Air cleaner is new. These plugs have about 900 recent miles in them. The car does not blow out smoke(blue or white) upon cold start.. sometimes a small amount of steam from water evaporation as it comes up to temp.
I do seem to be losing some oil lately, which is new. I've only driven the car a total of about 1,000 miles since getting her.
The only thing I can think of is either a couple of bad valve seals, or fuel leaking down from carb. Maybe something totally benign. Thoughts?
Thanks for taking a look.
Alex
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