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Engine Rear main seal still dripping, been replaced twice!!

  • Thread starter Thread starter AnthonyA1234
  • Start date Start date Jan 5, 2023
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AnthonyA1234

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#1
  • Jan 5, 2023
  • #1
Took the fox to a shop to get the leaky rear main seal replaced. When I got it back it was still leaking. Shop owner said no problem I took it back and he changed it again for me. I have the car again now and it’s still dripping! Are there any tips for this or maybe a certain rear main seal to buy that I should now about or bring to him when I go the third time?
 

evintho

20+ Year Stangneter
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Jan 5, 2023
#2
  • Jan 5, 2023
  • #2
Copied this from my build thread. So far, it seems to have worked well!

Ford 5.0's are notorious for leaking rear main seals. I want to prevent that at all costs. Installed Fel-Pro's crankshaft repair sleeve.
Fel-Pro 16250 crank repair sleeve
I ran a thin film of this on the inside before I tapped it on....
Loctite 518 Flange Sealer
I also used Ford Racings RMS to button it all up.....
Ford Racing rear main seal
When I install the flywheel I'll slather thread sealant on the bolts and that should prevent any RMS leaks.

 
Reactions: Wayne Waldrep and AnthonyA1234

AnthonyA1234

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#3
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Perfect! That’s good to know. I should have done more research on this before hand, I didn’t know it was such a common issue. Would you happen to have the part number for the installation tool for that repair sleeve?
 

AnthonyA1234

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#4
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And this is the thread sealant I should use on the flywheel bolts correct?
Amazon product ASIN B0002UEOP0View: https://www.amazon.com/Permatex-59214-Temperature-Thread-Sealant/dp/B0002UEOP0
 

Mustang5L5

That is…until I whipped out my Bissell
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#5
  • Jan 5, 2023
  • #5
AnthonyA1234 said:
Would you happen to have the part number for the installation tool for that repair sleeve?
Click to expand...

Felpro 16300



I did the same repair on my car. Seal only eventually leaked shortly after. I used the 16250 sleeve and so far so good (fingers crossed). I did see a slight wear line on my crank which is why i went with the sleeve
 

AnthonyA1234

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Mustang5L5 said:
Felpro 16300



I did the same repair on my car. Seal only eventually leaked shortly after. I used the 16250 sleeve and so far so good (fingers crossed). I did see a slight wear line on my crank which is why i went with the sleeve
Click to expand...
I don’t know if it got discontinued or if it’s out of stock everywhere but no one has it. This eBay listing of a different branded tool is all I can find but the bio says it’s the same. Does it look like how yours looked?

Crankshaft Repair Sleeve Tool Ford 5.0 for Rear Seal Compatible w/ FelPro 16300 | eBay

Interchange for the FelPro 16300 tool. They are a division of Dana. This is compatible to the FelPro 16300 installation tool. FelPro #: 16300. After many years and miles the rear main seal can wear a small groove into the end of the crankshaft.
www.ebay.com
 

Noobz347

Stangnet Facilities Maint Tech... Er... Janitor
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That is the tool and the sleeve.
 

evintho

20+ Year Stangneter
Nov 12, 2003
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#8
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AnthonyA1234 said:
And this is the thread sealant I should use on the flywheel bolts correct?
Amazon product ASIN B0002UEOP0View: https://www.amazon.com/Permatex-59214-Temperature-Thread-Sealant/dp/B0002UEOP0
Click to expand...
Yes, that's the same sealant I used. Make sure you get the flange sealant to seal the repair sleeve also.
No need to spend $40 on the repair tool. A five dollar 4" PVC cap does the same job.
 

Potomus Pete

I'm still waiting for the fully nude shots
5 Year Member
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#9
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  • #9
Let us know Anthony. I have done a couple RMS also and still have a dripping mess. Soon I am pulling this transmission again and doing a sleeve. I need a reason to feel good about pulling this tranny again.
 

Mustang5L5

That is…until I whipped out my Bissell
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43,260
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Jan 5, 2023
#10
  • Jan 5, 2023
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AnthonyA1234 said:
I don’t know if it got discontinued or if it’s out of stock everywhere but no one has it. This eBay listing of a different branded tool is all I can find but the bio says it’s the same. Does it look like how yours looked?

Crankshaft Repair Sleeve Tool Ford 5.0 for Rear Seal Compatible w/ FelPro 16300 | eBay

Interchange for the FelPro 16300 tool. They are a division of Dana. This is compatible to the FelPro 16300 installation tool. FelPro #: 16300. After many years and miles the rear main seal can wear a small groove into the end of the crankshaft.
www.ebay.com
Click to expand...


It does look like the tool has been discontinued.

I no longer have mine, but that’s what it looked like. Wish I still had it as I could whip up a CAD dwg.
 

limp

wrap a little cheese around it and its a done
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#11
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The tool is nothing special ( except the price) looks like a piece of pipe the correct diameter to hammer the seal on....
Are you sure its your crank seal? Do you have sealant on your crank bolts?? They can leak also.....
 

Bullitt347

I have been doing it wrong this whole time
15 Year Member
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#12
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  • #12
Make sure your PCV is working correctly. If it is not, it can allow to much crankcase pressure to build up.
 
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Mustang5L5

That is…until I whipped out my Bissell
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#13
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limp said:
The tool is nothing special ( except the price) looks like a piece of pipe the correct diameter to hammer the seal on....
Click to expand...

It’s a peice of Delrin plastic, but you are right. It’s nothing special.

It was also $10/delivered from Amazon when I bought mine.
 

limp

wrap a little cheese around it and its a done
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#14
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Mustang5L5 said:
It’s a peice of Delrin plastic, but you are right. It’s nothing special.

It was also $10/delivered from Amazon when I bought mine.
Click to expand...
I need to look at mine, pretty sure it is metal.... I remember mine being over $50 including the seal...
 

96pushrod

I think they're a little easier to get off
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#15
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  • #15
Repair sleeve is the way to go. The last one I did I didn’t use any install tool or anything, just tapped it in nice and square with stuff I had sitting around the shop. Don’t forget some seal retaining compound around the id of the sleeve.
 
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1992MustangGT

15 Year Member
Sep 6, 2008
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Jan 7, 2023
#16
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Hey guys I just stumbled across this thread and I had a question about the rear main seal. I just replaced my clutch on my 92 GT and while I had it apart I replaced the rear main seal. I'm having the same problem as everyone else; my brand new seal is leaking. So after reading this thread I think I'm going to attempt this project again and use the sleeve. However here's my question. The rear main seal I used is Felpro 2941, but you used the Ford Racing M-6701-B302 seal. I noticed the seal I used is more money, but that may be due to it coming with the plastic installation sleeve to help slide it over the crank without damaging the seal lip. Is one of these seals better than the other one? Which would you suggest I use? Did the Ford Racing seal come with the installation sleeve?
 

Noobz347

Stangnet Facilities Maint Tech... Er... Janitor
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  • Jan 7, 2023
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1992MustangGT said:
Hey guys I just stumbled across this thread and I had a question about the rear main seal. I just replaced my clutch on my 92 GT and while I had it apart I replaced the rear main seal. I'm having the same problem as everyone else; my brand new seal is leaking. So after reading this thread I think I'm going to attempt this project again and use the sleeve. However here's my question. The rear main seal I used is Felpro 2941, but you used the Ford Racing M-6701-B302 seal. I noticed the seal I used is more money, but that may be due to it coming with the plastic installation sleeve to help slide it over the crank without damaging the seal lip. Is one of these seals better than the other one? Which would you suggest I use? Did the Ford Racing seal come with the installation sleeve?
Click to expand...
With a new sleeve installed, you would likely end up with similar results from either.
 

evintho

20+ Year Stangneter
Nov 12, 2003
683
245
73
Santa Rosa, CA.
Jan 7, 2023
#18
  • Jan 7, 2023
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Looks like the FelPro piece is made out of teflon instead of rubber. Sounds like it's hard and dry and easily destroyed if not installed properly. Check out 'customer reviews' towards the bottom of the page......
Amazon product ASIN B000CMEUG6View: https://www.amazon.com/Fel-Pro-2941-Rear-Engine-Main/dp/B000CMEUG6


My Ford Racing seal was way cheaper and easily installed using the aforementioned PVC cap however, you do have to be very careful and delicate when installing.
 
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1992MustangGT

15 Year Member
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#19
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Evintho--So basically you're saying the rubber Ford Racing seal is better quality and would seal better than the teflon Fel Pro seal?
 

96pushrod

I think they're a little easier to get off
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#20
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1992MustangGT said:
Evintho--So basically you're saying the rubber Ford Racing seal is better quality and would seal better than the teflon Fel Pro seal?
Click to expand...
Get the viton rear main seal, like the ford racing one.

I’ve never been a fan of the Teflon ones. Had good luck with rubber.
 
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