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Rear Main Seal

Rear Main Seal

Chad Bolles

BJ Kroppe asks:

I am about to commence to install the rear main oil seal in my 1982 4.2L engine, and I have some questions:

  1. The service manual says to use a sizing tool, tool number JD 17B. Is this really required? If it is, where can I get the tool, since I haven't seen it in XKU, SICP, Welsh's or Terry's catalog. Anyone in the southeast Michigan/northern Ohio area who would be willing to loan me their tool? You would have my word as a Jag-lover that you would get it back.
  2. The manual says to use a small amount of "colloidal graphite" on the surface of the rear main seal when installing it. What is this stuff and where can I buy it?

Thanks in advance for any info.

Save yourself time and go to NAPA and ask for the rear main seal for a 460 Ford engine, if I remember right it is already impregnated with a graphite material, also a better seal. A little longer than the stock seal so you will have to trim it. NAPA part No JV-730.

As far as the sizing tool, good luck. Never have used one and have so far had no leaks, and I build engines all the time. I always take the seal and lay on a flat working surface then take a small hammer and make it look like this >. When shaped so it will fit the seal track with ease. Start on one side of the track, leaving a small amount of seal sticking out of the block or cap, now with the handle of the small hammer start working the seal into the track. When you get to the other side trim off the excess, but leave a VERY small amount extra. I also coat the seal track with a nonhardning gasket sealer NOT SILICONE.

You might want to practice on another seal first.

Chad Bolles Jaguar Performance,Inc 306 Valcour Rd Columbia SC 29212USA 803 798 3044

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