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Old 06-25-2012, 09:38 PM
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CORRECTION: Yes, the all of the spark plug electrodes did have oil on them both times when they were removed and cleaned. I had my terminology wrong, sorry.

Originally Posted by cobalt327
That's good, the oil leak is external and there's no need to fret any more about the rings, valve seals, PCV, or intake gaskets. Be sure to go back and retighten the intake a few times after it heat cycles until the bolts take a set.
Might be an issue now? Piston rings, perhaps?

Originally Posted by cobalt327
You'll want to locate the oil leak that's getting into the plug recesses. It could be coming from the front of the engine and blowing back from the fan. It helps to have the engine clean. Another thing you can do that will sometimes help locate a leak is to put a piece of cardboard under the engine after running it. See where the drips are concentrated and look up- and possibly forward- from the heaviest spots.
I did put a large aluminum drip tray with kitty litter under the truck for a couple of days to see where oil might be leaking from. It had dripped in three or four spots but I couldn't trace it back to anything. I paid special attention to valve covers since they had leaked before but those areas appeared to be oil free. The oil pan gasket also appeared to have no leaks.
Originally Posted by cobalt327
The leaks are concentrated more towards the rear of the engine bay. At this point, I am leaning towards rear main seal. But that obviously wouldn't explain the oil getting into the spark plug threads.

No need to remove anything. What you want to see is if the plug electrode/porcelene are fouled or discolored more on one side of the electrode than the other. If they are, the next thing will be to determine what valve the fouled side is facing. The valve sequence on a SBC is:

E I I E E I I E. A spark plug will sit where every numeral is. So looking at the sequence, you can see if the plug for cylinder #1 has more deposits on the left side when it's fully tightened into the head, that the deposits are coming from the exhaust guide.

If there is no "worse" side to the plugs and they look to be coloring equally, that's good and nothing need be done.
Thanks for that break down, it helps tremendously. I'll take sharpie to the plugs before putting 'em back in.

Originally Posted by cobalt327
One thing about the vacuum advance- be sure to reattach the vacuum hose to it after setting the timing. When an engine pings, it'll sound like a faint metallic ticking. Some describe it as marbles in a can- but the detonation would need to be pretty severe for it to be that bad, IMHO. You'll notice it more when you load the engine in a higher gear, like going up an incline or hill.
Ok, that's the sound I'll keep an ear out for then.

Originally Posted by 123pugsy
My mistake.

Use the arrow buttons and it will advance the light until you see the mark on the balancer line up with the timing tab. Its real simple. Play around with it and you'll see. I can't set the VCR time but I can use that light.
Ah, that's what I suspected, but for some reason I thought that feature was for the distributor-less ignition systems.

Ok, got my list of what to do next: sharpie the plugs, torque down the intake manifold bolts, throw on the carb; check the PCV and trans modulator components, run it for a while, time it, and check the plugs again. Sounds good?
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