Are these Plugs ok?

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Mustang1964s
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Are these Plugs ok?

Post by Mustang1964s » Sun Aug 28, 2022 1:14 pm

I have been running these plugs the last few years Been on several T Parties.
They seem like they are pretty much normal except number 4 cylinder.
I used a brass brush and did a quick clean up.
Two questions. 1) Does this look like the carb is adjusted ok?
2) What can I use to keep the spark plugs and head from rusting?

CYL 1
IMG_4182.jpg
CYL 2
IMG_4183.jpg
CYL 3
IMG_4184.jpg
CYL4
IMG_4185.jpg


TXGOAT2
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Re: Are these Plugs ok?

Post by TXGOAT2 » Sun Aug 28, 2022 1:28 pm

The rust is due to water standing in the cylinder head depressions around the plugs. Rainwater can leak through the hood hinge or water can get in when washing the car. Dry the standing water out with a clean rag and don't permit water to stand. The plug looks OK, but dirty. I would not use a wire brush on any spark plug. The plug insulator at the plug tip is a porous ceramic that can collect metal from a wire brush, especially a brass one. The embedded metal particles will tend to short out the plug. Soak the plugs in solvent, then gently scrape out the area around the insulator and up in the plug body with a sliver of hardwood or a plastic wire tie. Do not sandblast the outside (glazed) part of the insulator. It's OK to sandblast the gap end of the plug, but if you do, be sure to get all the sand out. The center electrode should be flat, and the end of the side electrode should be flat and square, like a new plug. If they are rounded, they can be carefully filed to shape with a small small file. Keep any filing to a minimum. Finish up by setting the gap. One of the round wire type gauges works very well on used plugs. .028 to .030 usually works for a setting. If you start the car on magneto, .026 to .028 may give better results.

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George House
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Re: Are these Plugs ok?

Post by George House » Sun Aug 28, 2022 3:04 pm

Your spark plugs are OK. I clean all metal parts on a bench grinder with fine bristles. Then I spend more time with the upper threads and hex on the bench grinder to bare metal. Then I brush ospho on and let dry. Then I mask the upper porcelain and lower threads and spray clear lacquer. If you keep water out of the head depressions where plugs are installed, they’ll look purty for years.
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Jerry VanOoteghem
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Re: Are these Plugs ok?

Post by Jerry VanOoteghem » Sun Aug 28, 2022 3:29 pm

The answer to the question, "Are these plugs ok?" is another question. How does the car run? Of course, that assumes everything else is in top shape ;)

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CudaMan
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Re: Are these Plugs ok?

Post by CudaMan » Sun Aug 28, 2022 3:59 pm

I see a lot of carbon, have you tried leaning out the carburetor in small increments to see if the car will run OK with a leaner mixture?
Mark Strange
Hillsboro, MO
1924 Cut-off Touring (now a pickup)

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