Compression Checks

[rfitzpatrick]

I've a '31 Pickup bought from a local Club-Member two years ago. Doing a compression check and found this: Number 1 & 3 read 60 PSI with numbers 2 & 4 are 59.
My original concern was the number 2, as it shows an oilie residue/a build up on the bottom of the plug when I have them all out for cleaning/resetting. My plugs are Autolite 3076. I have no issues with the way the engine performs. Is anything going on here?
Thanks Guys

[Patrick L.]

Sounds fine to me. I like Autolites, 3076 are a tad cool but 3077 [which I prefer] are hard to find nowadays.

[Dick Steinkamp]

You could have worn valve guides in that cylinder which is allowing a little oil in. That condition wouldn't show up on a compression check.

[rfitzpatrick]

Originally Posted by Dick Steinkamp

You could have worn valve guides in that cylinder which is allowing a little oil in. That condition wouldn't show up on a compression check.

That would make sense to me since I have swapped no 2 plug to different cylinders when cleaning/gaping.
Thanks

[40 Deluxe]

Originally Posted by Dick Steinkamp

You could have worn valve guides in that cylinder which is allowing a little oil in. That condition wouldn't show up on a compression check.

Or, the oil control ring in that cylinder is damaged and letting oil by, while the compression rings are still good.

[Dick Steinkamp]

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In any case, if the plug doesn't foul and with that good compression, no problem

[BILL WILLIAMSON]

Why the hell are you diddling with a car that runs FINE?????? You'll wear out the bolt THREADS!!!
Bill W.

[rfitzpatrick]

Originally Posted by BILL WILLIAMSON

Why the hell are you diddling with a car that runs FINE?????? You'll wear out the bolt THREADS!!!
Bill W.

How did you know: I ran the check - twice !?