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#@%&!* REAR MAIN SEAL

  • Thread starter Thread starter ss93cobra
  • Start date Start date May 26, 2005
S

ss93cobra

Founding Member
Apr 10, 2002
1,422
1
0
Wilmington NC
May 26, 2005
#1
  • May 26, 2005
  • #1
Hey everyone. here's one for you. Stock 88 block, Ford Racing stock spec. crankshaft, main caps, etc. The rear seal starts to leak after @ 15 minutes of idling. Motor was just put back together as well. Oil pressure of 60 at an idle, 80 at 2,000 rpm. Yeah, a little high but I doubt its the culprit here. Running a breather, no blowby, using a pcv and that's it. After it gets good and hot, the rear seal starts to leak. Both seals used were from Ford Racing and Ford and both leaked after @ 15 minutes of running. Seems to be coming from the exterior edge of the seal, not seal to crank. Nice steady drip. Seal installer was used as well. Even squirted some silicone on the edges when the second one was installed. Block was inspected for a nick or scratch as well. It's Any thoughts? Anybody have a part # for a seal with a slightly larger o.d. ?
 

tunedin302

I AM the law!!!
Jul 29, 2004
1,251
2
36
Pennsylvania
May 26, 2005
#2
  • May 26, 2005
  • #2
Fel-pro teflon seal and silicone - no leaks. Does your crank need to be sleeved?
 
S

ss93cobra

Founding Member
Apr 10, 2002
1,422
1
0
Wilmington NC
May 26, 2005
#3
  • May 26, 2005
  • #3
Have you got a # for the Felpro seal? The crank is brand new as well and better not need sleeved. Plus, the leak appears to be coming from the outside edge of the seal, not the inside.
 

tunedin302

I AM the law!!!
Jul 29, 2004
1,251
2
36
Pennsylvania
May 26, 2005
#4
  • May 26, 2005
  • #4
Summit racing

Teflon seal
Part# FPP-2941
Price: $37.99
 
S

ss93cobra

Founding Member
Apr 10, 2002
1,422
1
0
Wilmington NC
May 26, 2005
#5
  • May 26, 2005
  • #5
Thanks! Keep your fingers crossed. BTW, I forgot to mention it's a 306 with a Vortech 12-14lb pulley on her with Roush 200 heads and an Anderson cam. It shouldn't matter though since it's never seen boost yet, all was at idle or slightly above idle.
 

tunedin302

I AM the law!!!
Jul 29, 2004
1,251
2
36
Pennsylvania
May 26, 2005
#6
  • May 26, 2005
  • #6
You probably already know this ... but put the silicone on the block/seal and then let it sit overnight before starting to ensure a good seal. Rick91gt is the guru of this stuff ... thanks to him my rear main no longer leaks
 

HISSIN50

"How long does it take to get help in here?
15 Year Member
Nov 29, 1999
31,179
33
129
May 26, 2005
#7
  • May 26, 2005
  • #7
Autozone here sells the Fel-Pro teflon RMS's for 20 bucks.

good luck.
 

Ranchero5.0

The Voice of Reason
Jan 1, 1999
5,306
0
76
Hagerstown MD
May 26, 2005
#8
  • May 26, 2005
  • #8
Also during assembly did you put a dab of RTV between the rear cap and the block? May be leaking from between the mating surface.

Jamie
 

DMAN302

My mom says thanks for the pearl necklace.
Nov 8, 2003
2,120
2
59
windsor, Canada
May 26, 2005
#9
  • May 26, 2005
  • #9
I hear you, I really do..245 miles on the mill..just a baby, and what do I find on the tranny back plate..a drop of oil..where from...the rear main, yup a leak. I have chosen to ride it out untill winter when I pull the tranny for a rebuild..however my car only sees about 2-3 hundred miles a month. Good luck no matter what you decide to do.
 
S

ss93cobra

Founding Member
Apr 10, 2002
1,422
1
0
Wilmington NC
May 27, 2005
#10
  • May 27, 2005
  • #10
New seal's in, not a sign of a leak yet! Keep your fingers crossed!
 

Stang8URMPRT

Active Member
Dec 28, 2003
1,100
1
38
Daytona Beach, FL
May 27, 2005
#11
  • May 27, 2005
  • #11
Woohoo!
 

Rick 91GT

Mustang Master
Nov 29, 1999
9,692
95
99
PA
May 27, 2005
#12
  • May 27, 2005
  • #12
tunedin302 said:
You probably already know this ... but put the silicone on the block/seal and then let it sit overnight before starting to ensure a good seal. Rick91gt is the guru of this stuff ... thanks to him my rear main no longer leaks
Click to expand...

 
S

ss93cobra

Founding Member
Apr 10, 2002
1,422
1
0
Wilmington NC
May 27, 2005
#13
  • May 27, 2005
  • #13
Stang8URMPRT said:
Woohoo!
Click to expand...
 

tunedin302

I AM the law!!!
Jul 29, 2004
1,251
2
36
Pennsylvania
May 27, 2005
#14
  • May 27, 2005
  • #14
 
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