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  • 1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk-
  • Fox 5.0 Mustang Tech

rear main seal, have questions....

  • Thread starter Thread starter jmd2914
  • Start date Start date Nov 24, 2005
J

jmd2914

Founding Member
Sep 6, 2002
937
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0
Napa, California
Nov 24, 2005
#1
  • Nov 24, 2005
  • #1
alright, im in the middle of my clutch install, i just pulled my starter off and there is oil and stuff caked all over the inside, I'm thinking my rear main seal is shot. should i replace it while my tranny is dropped? and how much is one going to cost?
 

feifong

New Member
Apr 4, 2005
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mesa
Nov 24, 2005
#2
  • Nov 24, 2005
  • #2
now is a good chance like 8 bux for a seal
 
J

jmd2914

Founding Member
Sep 6, 2002
937
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0
Napa, California
Nov 24, 2005
#3
  • Nov 24, 2005
  • #3
how hard is it to replace?
 

HISSIN50

"How long does it take to get help in here?
15 Year Member
Nov 29, 1999
31,179
34
129
Nov 24, 2005
#4
  • Nov 24, 2005
  • #4
Use a removal tool (seal puller) to get the old seal out and then press the new one in (a seal driver works, as do shadetree methods).

I would do the pilot bearing while in there (if getting a new one, make sure and explicitly ask for a pilot bearing and not a pilot bushing). One can use a slide hammer to remove the pilot bearing or hydraulics also work. It can go smooth or be a real PITA.

Good luck.
 
J

jmd2914

Founding Member
Sep 6, 2002
937
0
0
Napa, California
Nov 24, 2005
#5
  • Nov 24, 2005
  • #5
i have new pilot bearing to replace the old bushing, i need the removal tool for that, not for the rear main seal right? how complicated is it to replace the rear seal?
 

HISSIN50

"How long does it take to get help in here?
15 Year Member
Nov 29, 1999
31,179
34
129
Nov 24, 2005
#6
  • Nov 24, 2005
  • #6
In my last post, I had added the pilot bearing part in the middle of typing and I messed up the pasting, so the wrong description was with the wrong item.
I kinda fixed it.

So yeah, a seal puller works for the seal (though you can mangle it out if you are careful). I have made them fold up before (like a Vee) and then removed them. You just gotta be real careful. Also, putting a couple screws through the seal and then yanking on them can work too.
 
D

Doh

New Member
Nov 25, 2005
19
1
3
Nov 25, 2005
#7
  • Nov 25, 2005
  • #7
easiest way to replace remain is to loosen the rear main cap on the crank remove rear main seal (pry carefully) then just tap the new one in. mind you its hard to get at the main bearing cap with a pan on and it really sux you cant get the pan off with the engine in the car. i just replaced mine but i had the 302 removed from my pick-up already so it was pretty easy. i guess you dont have to loosen rear cap but i was told it makes it easier.
 

Michael Yount

Mustang Master
Apr 10, 2002
9,039
6
79
Charlotte, NC
Nov 25, 2005
#8
  • Nov 25, 2005
  • #8
As long as you're in there, replacing the rear main is a sound idea. However, a bad seal may not be the cause of the leak there. Too much crankcase pressure frequently pushes oil past perfectly good seals.

So once the new seal/clutch is in and you've got it running, check out your PCV system to be sure it's in good working order and is adequately ventilating the crankcase.
 

04sleeper

Founding Member
Jun 22, 2002
2,674
14
89
Dallas, TX
Nov 25, 2005
#9
  • Nov 25, 2005
  • #9
Good advise there Mike.

I would also add to be sure you oil the seal and crank a little before installing it so it doesn't tear up.
 

5spd GT

"the 5.0 owns all"
Founding Member
Aug 7, 2002
9,516
6
99
Arkansas
Nov 25, 2005
#10
  • Nov 25, 2005
  • #10
Instructions say to install dry and some say to lube it up. Lubing it up does make sense so the inner ring doesn't kink. That is where I have a problem installing them is that the inner ring trys to kink
 

04sleeper

Founding Member
Jun 22, 2002
2,674
14
89
Dallas, TX
Nov 25, 2005
#11
  • Nov 25, 2005
  • #11
If you install it dry then the minute you turn the engine over the crank will tear the seal.

I have never read anywhere saying install it dry.
 

Michael Yount

Mustang Master
Apr 10, 2002
9,039
6
79
Charlotte, NC
Nov 25, 2005
#12
  • Nov 25, 2005
  • #12
Any rubber/neoprene seal on a moving part usually benefits from a bit of light grease or vaseline to keep it supple and allow it to move without binding. And whatever you do, don't try to 'improve' things by adding some rtv in there.
 

5spd GT

"the 5.0 owns all"
Founding Member
Aug 7, 2002
9,516
6
99
Arkansas
Nov 25, 2005
#13
  • Nov 25, 2005
  • #13
If the "improving" comment was made to me, I will not add rtv "in there"...not very smart. I will on the outside.
 
M

Mattys5Oh

Founding Member
Sep 28, 2002
216
0
0
Western, Mass
Jun 8, 2006
#14
  • Jun 8, 2006
  • #14
Bringing this back from the dead as it has some useful info. I have my engine on an engine stand and I'm trying to replace my rear main seal. I don't think there is enough clearence to do it while it's on the stand, so i might wait until right before I drop it in and it's on the engine hoist. But that's not my question. I want to know if anyone has any pictures of removing the rear main seal? I have a new seal and it looks nothing like the area around the back of the crank. I am very nervous when it comes to doing something the first time (as this is the first engine I've really had apart) so I really do not want to f this up or the crank!
 
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