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New Rear Main Seal Leaking

  • Thread starter Thread starter gnx547
  • Start date Start date Aug 31, 2013

gnx547

Member
Sep 26, 2006
283
1
19
Aug 31, 2013
#1
  • Aug 31, 2013
  • #1
I was about to put on the flywheel and I notice the rear main seal has a small leak in the bottom. The rear main seal is new with zero miles and the engine is new and never been started yet. I don't understand why it is slightly leaking? Any ideas?


 

madspeed

Colonel Mustard
Founding Member
Nov 29, 1999
8,914
1,332
204
a van down by the river
Aug 31, 2013
#2
  • Aug 31, 2013
  • #2
mine does the same...
 

mikestang63

SN Certified Technician
Aug 27, 2012
11,606
8,859
214
In the garage
Aug 31, 2013
#3
  • Aug 31, 2013
  • #3
could have been overtightened and warped, installed dry, could be a nick in the seal or in the cap from improper removal/install. Personally I install the teflon sleeve and FelPro rear main seal and have never had a leak.

Here's a good video of installing the seal properly with the teflon sleeve.

 
Last edited: Aug 31, 2013

Mustang5L5

That is…until I whipped out my Bissell
Mod Dude
Feb 18, 2001
43,244
17,924
224
Massachusetts
Aug 31, 2013
#4
  • Aug 31, 2013
  • #4
Never been run? It could be just residual seepage from the install. I'm not sure if that would suggest to me a leak.

When I did my rear main seal, it leaked for about 500 miles after the install. After that, it just stopped. I've done several oil changes since...def a full 5 quarts in there


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