Read my spark plugs

Hi all - these old plugs tell you anything I should be aware of? Is the oil on the threads normal?

Thanks for any feedback!

They look normal.

I’ve always found oil on the threads like that a mystery with my Ford V8’s. Does anyone really know where it comes from? You’d think if it were getting up there from below the rings the car would smoke like a demon.

Is the valve covers leaking? Small Block, FE?

351w. I don’t think the covers are leaking. At least nothing apparent.

The coloration looks pretty normal for worn plugs. However, the threads are a bit wet.

Do you have old style cork manifold gaskets? I believe they work better than new synthetic ones, but may need to be replaced or re-torqued - especially on the side where that bottom picture of plugs came from. Get a good low range inch/lb torque wrench (especially if you have aluminum covers) and you may have to set them a couple time following the suggested pattern to get them right.

Otherwise I think the plugs look fairly normal and does not appear to leak oil in the cylinders themselves.

The residue on the spark plug threads is because no one uses anti seize on tapered spark plugs (people have forgotten how technology works) so there is a slight bit of leakage around each one. The residue is a mixture of carbon and unburned fuel. To eliminate it use a bit of C5A or Nickle Eze on the threads next time plugs are installed.

Not quite “no one” Royce. I have always used “anti seize” on plugs for all of my toys and still do. Currently, Pole Cat has a leak in both rocker covers at the top. Don’t know about the bottom side but planning (winter project) on replacing with the cork as I tried the rubber, no joy. However, Pole Cat does not get that residue on the plug threads.

Just another vote for Anti Seize.

Royce/Gary thank you for the information on the Anti Seize, I always wondered where this oil was coming from, as my car doesn’t use any oil or smoke and there is always oil on the threads when I pull them.

Good stuff as always folks, thanks!!