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  • 1965 - 1973 Classic Mustangs -General/Talk-
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Where to Seal?

  • Thread starter Thread starter Mustang Jim
  • Start date Start date Mar 5, 2010

Mustang Jim

Founding Member
Nov 1, 2001
373
3
18
New Jersey
Mar 5, 2010
#1
  • Mar 5, 2010
  • #1
OK, so I'm pulling off the oil pan tomorrow morning and replacing the rear main seal. I picked up the rear seal tonight and I'm almost ready to go.

I know I'm supposed to put a dab of sealant at the cap when I assemble it, but where exactly? At the cap mating surface? Just a little?

I have some permatex red RTV that is supposed to be good up to 650F, so that should do it.

Thanks,
Jim
 

dennis112

15 Year Member
May 15, 2005
1,561
36
79
Amish Wonderland of Central PA.
Mar 6, 2010
#2
  • Mar 6, 2010
  • #2
The RTV goes specifically where the main cam meets the block register. Look closely at the ends of the main cap and you will see this bevel (thin shiney line) that goes the whole width of the main cap:



A light little dab will do ya in the block and you only need it toward the rear most area of the block .

Also, I am not fond of using the red high heat stuff on engine internals and prefer using Permatex Ultra Black.
 

Mustang Jim

Founding Member
Nov 1, 2001
373
3
18
New Jersey
Mar 6, 2010
#3
  • Mar 6, 2010
  • #3
Thanks Dennis. Your description and picture are very helpful. I will pick up some Permatex Ultra Black this morning.
 

Mustang Jim

Founding Member
Nov 1, 2001
373
3
18
New Jersey
Mar 6, 2010
#4
  • Mar 6, 2010
  • #4
Well, I dropped the pan and replaced the rear main seal. Not too bad at all. It only took me about 3 hours. While I was at it, I replaced the pilot bearing. That's all for this weekend. Next weekend I install the new flywheel, clutch and pressure plate. I can't wait!
 
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