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Teflon Rear Main Seal - Wrong part or hard to install?

  • Thread starter Thread starter 95BlackTan50
  • Start date Start date Apr 8, 2007

95BlackTan50

Member
Oct 28, 2004
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16
Apr 8, 2007
#1
  • Apr 8, 2007
  • #1
While my transmission is down I decided to replace my leaky rubber rear main seal. I bought a teflon one after reading some posts but I managed to damage it before I got it installed. The one on the left is the teflon one and the one on the right is the rubber one that I removed. The inner diameter of the teflon one is smaller and won't slide over the crank. Do I have the right part or is there some way to install this correctly? I've read that the teflon ones are hard to install.

I'll be picking up a new teflon one from Advance tomorrow and comparing it to a rubber one and the one that I got from Napa.

Thanks for any input on this. Barney.

 

_jb_

New Member
Mar 4, 2004
808
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0
Michigan, Berrien County
Apr 8, 2007
#2
  • Apr 8, 2007
  • #2
Did you put oil around the Teflon to help it slide on? Mine was a little tight but I had no problems with it.
 

95BlackTan50

Member
Oct 28, 2004
116
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Apr 8, 2007
#3
  • Apr 8, 2007
  • #3
No, I didn't put oil on the teflon side. It seemed like it was'nt even close to clearing the crank. It also seemed that the teflon was tapered in the wrong direction and it folded when I applied pressure. I'll be curious to see what the part from Advanced looks like.
 
C

cbarr300

Member
Jun 6, 2006
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goose creek, SC
Apr 9, 2007
#4
  • Apr 9, 2007
  • #4
Mine (felpro) came with a plastic sleeve that you slide over the crank. Then you just put it on the tapered side of the sleeve and slide it right on. As far as I know its better not to use oil on the teflon seals...maybe someone can confirm this?
 

94-302-vert

Active Member
Aug 16, 2004
1,947
2
36
NE CT
Apr 9, 2007
#5
  • Apr 9, 2007
  • #5
I would think to use oil. Oil is gonna get in there anyway...
 

95BlackTan50

Member
Oct 28, 2004
116
0
16
Apr 9, 2007
#6
  • Apr 9, 2007
  • #6
Ok, I just got the teflon rear main seal from Advance and it came with a plastic sleeve that it calls an installation tool. It says to use the sleeve to install the seal then remove it. It also has a smaller taper than the one I got from Napa.

Now for the really stupid question. When I install the sleeve, which end should be facing into the engine and which end should be facing me when I get done?

I think this side faces out.


and this side goes into the engine.


Have I got it right or not?

Thanks for straightening me out.

Barney
 

_jb_

New Member
Mar 4, 2004
808
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0
Michigan, Berrien County
Apr 9, 2007
#7
  • Apr 9, 2007
  • #7
I think you have it right, but I can't remember. I want to say mine had the "lines" facing the transmission...
 
C

cbarr300

Member
Jun 6, 2006
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goose creek, SC
Apr 9, 2007
#8
  • Apr 9, 2007
  • #8
you would be correct
 

4G-KDMP

10 Year Member
Jul 23, 2005
935
19
39
CA
Apr 10, 2007
#9
  • Apr 10, 2007
  • #9
i'll be replacing mine sometime this week, thanks for the info.
 

95BlackTan50

Member
Oct 28, 2004
116
0
16
Apr 10, 2007
#10
  • Apr 10, 2007
  • #10
Ok, I got it in last night. The plastic sleeve worked out well. I also found a cheap tool that made it easy to install. I got one of those 4" threaded PVC end caps, the one with the square piece on top that's normally used to put a pipe wrench on. The diameter fit perfectly on the rear main seal and plastic seal and the square top was perfect for tapping with a hammer. Hopefully that took care of the oil leak.

Thanks for all the help.
 

4G-KDMP

10 Year Member
Jul 23, 2005
935
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39
CA
Apr 11, 2007
#11
  • Apr 11, 2007
  • #11
so the part w/ the spring goes inside toward the crank right, not the flat part?
 

ShortThrow50

Member
Oct 22, 2006
923
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16
Pa
Apr 11, 2007
#12
  • Apr 11, 2007
  • #12
good info
 
K

Kenny_Stang

New Member
Jun 2, 2000
31
0
0
Apr 11, 2007
#13
  • Apr 11, 2007
  • #13
Do you have a part # for this? I'll be replacing mine when I change my clutch. Thanks.
 

95BlackTan50

Member
Oct 28, 2004
116
0
16
Apr 12, 2007
#14
  • Apr 12, 2007
  • #14
Kenny_Stang said:
Do you have a part # for this? I'll be replacing mine when I change my clutch. Thanks.
Click to expand...

I got the rear main seal at Advance Auto Parts, part number BS40644.

BS40644 Link

4G-KDMP said:
so the part w/ the spring goes inside toward the crank right, not the flat part?
Click to expand...

Correct. The part that I got didn't have a spring, but the flat part does not go inside the engine.
 
9

95_5.0_stang

New Member
Apr 16, 2005
172
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0
Lansing, MI.
Apr 12, 2007
#15
  • Apr 12, 2007
  • #15
Yea, I just recently rebuilt a motor and used the teflon RMS. That little plastic installation tool works great. And I don't seem to have any leaks as of yet. Just drove it to Florida and put around 3000 miles on the motor. Don't use any oil on the crank/seal surface, but what I did was put a small amount of black permatex around the outside of the seal.
 

4G-KDMP

10 Year Member
Jul 23, 2005
935
19
39
CA
Apr 12, 2007
#16
  • Apr 12, 2007
  • #16
95BlackTan50

thank you.
 

5spd GT

"the 5.0 owns all"
Founding Member
Aug 7, 2002
9,516
6
99
Arkansas
Apr 12, 2007
#17
  • Apr 12, 2007
  • #17
Yep, I have replaced the seals before. The 'spring' side goes towards the engine and the 'flat' side faces towards the transmission. Good Luck! Be patient when installing it. Don't let the inside lip get 'twisted'....
 
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