Engine New Rear Main Seal leaks

Mystang66

Member

Jul 23, 2011

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19

Minneapolis, MN

Feb 26, 2021

#1

• Feb 26, 2021

• #1

Just got my 1985 302 HO back running after pulling the tranny to replace the rear main seal Fel Pro seal BS40620 and repair sleeve 16250. The first time I start it and it’s leaking worse than before the repair. Any thoughts? If I have to go through all of this again, I want to make sure it’s right.

 

nickyb

I gotta say i never painted my nuts, Never Ever

15 Year Member

Apr 3, 2009

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Feb 26, 2021

#2

• Feb 26, 2021

• #2

Did you use thread sealer on the flywheel bolts?

 

Mystang66

Member

Jul 23, 2011

76

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Minneapolis, MN

Feb 26, 2021

#3

• Feb 26, 2021

• #3

nickyb said:

Did you use thread sealer on the flywheel bolts?

Click to expand...

Yes, I did. Threadlocker blue.

 

nickyb

I gotta say i never painted my nuts, Never Ever

15 Year Member

Apr 3, 2009

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Feb 26, 2021

#4

• Feb 26, 2021

• #4

No not thread locker, sealer. The crank bolt holes go threw and need to be sealed,ask me how I know.

 

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Mystang66

Member

Jul 23, 2011

76

16

19

Minneapolis, MN

Feb 26, 2021

#5

• Feb 26, 2021

• #5

No, I just used threadlocker, not sealant.

 

nickyb

I gotta say i never painted my nuts, Never Ever

15 Year Member

Apr 3, 2009

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Feb 26, 2021

#6

• Feb 26, 2021

• #6

My first time I did the same, and you see where that got me. I was to lazy to do it over and drove 100,000 miles before replacing the clutch again and then I did it right.

 

S

Specracer

Active Member

Nov 24, 2020

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SE MA

Feb 28, 2021

#7

• Feb 28, 2021

• #7

This thread scares me. Did the same thing, but I did 3 things differently, Ford seal, Wurth gray RTV on flywheel bolts, and loctite under the repair sleeve. I still have not yet started the car (I had engine out, slowly getting things back together). Did smoke the engine, looking for leaks, did not seem to be any from the rear main. Fingers crossed.

 

SLOWBRA

Founding Member

Oct 30, 2001

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Feb 28, 2021

#8

• Feb 28, 2021

• #8

Specracer said:

This thread scares me. Did the same thing, but I did 3 things differently, Ford seal, Wurth gray RTV on flywheel bolts, and loctite under the repair sleeve. I still have not yet started the car (I had engine out, slowly getting things back together). Did smoke the engine, looking for leaks, did not seem to be any from the rear main. Fingers crossed.

Click to expand...

I feel you. I will be going down this journey myself soon and have always understood that "rear mains will always leak".. lol. Every 5.0/5.8 I've had leaked. Would be nice to find a solution that gives us our best chance.

 

Potomus Pete

I'm still waiting for the fully nude shots

5 Year Member

Mar 7, 2019

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Feb 28, 2021

#9

• Feb 28, 2021

• #9

Me too I replaced my seal with a new clutch. Started dripping right away. I need a sleeve, and would like some reviews on how some of your repairs

 

mikestang63

SN Certified Technician

Aug 27, 2012

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Feb 28, 2021

#10

• Feb 28, 2021

• #10

I put a small amount of Right Stuff on the rear main seals when I do them.

 

Mustang5L5

That is…until I whipped out my Bissell

Mod Dude

Feb 18, 2001

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Feb 28, 2021

#11

• Feb 28, 2021

• #11

I just did mine with a new Ford seal and Felpro sleeve.

fingers crossed

 

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Gearbanger67

5 Year Member

Dec 12, 2017

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Mar 1, 2021

#12

• Mar 1, 2021

• #12

Mustang5L5 said:

I just did mine with a new Ford seal and Felpro sleeve.

fingers crossed

Click to expand...

X2

 

pats91

15 Year Member

Mar 6, 2007

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Gladstone, MO

Mar 1, 2021

#13

• Mar 1, 2021

• #13

Gearbanger67 said:

X2

Click to expand...

X3
I used the Fel-Pro sleeve and rear main a couple of years ago (along with a new pan gasket) and no leaks 5K miles later. At least from the Rear Main anyway.

 

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91GTstroked

15 Year Member

Jun 14, 2007

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Mar 2, 2021

#14

• Mar 2, 2021

• #14

I'm subbing. I plan on replacing my leaky rear main seal along with a new clutch. Do you guys have part numbers for what you used?

There should be a write up on this with detailed pictures if there is a solution.

 

S

Specracer

Active Member

Nov 24, 2020

71

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28

SE MA

Mar 2, 2021

#15

• Mar 2, 2021

• #15

SLOWBRA said:

I feel you. I will be going down this journey myself soon and have always understood that "rear mains will always leak".. lol. Every 5.0/5.8 I've had leaked. Would be nice to find a solution that gives us our best chance.

Click to expand...

Im only a few days from starting it, I hope. The crank was perfect, car only has 8k miles, but used the sleeve anyway.

BTW how are the 00R tanks coming along (yes Im the same guy that has been asking elsewhere, ha ha)?

 

Potomus Pete

I'm still waiting for the fully nude shots

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Mar 2, 2021

#16

• Mar 2, 2021

• #16

91GTstroked said:

I'm subbing. I plan on replacing my leaky rear main seal along with a new clutch. Do you guys have part numbers for what you used?

There should be a write up on this with detailed pictures if there is a solution.

Click to expand...

Your right , thats why we are waiting on you guys. Can't wait to see them.

 

Mustang5L5

That is…until I whipped out my Bissell

Mod Dude

Feb 18, 2001

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Mar 2, 2021

#17

• Mar 2, 2021

• #17

I thought I had the part numbers in my progress thread, but I looked it up.

for the rear main, there are a few. Pull up Rockauto and there are 10 or so to pick from. The Ford one is M-6701-B302.

install varies. I rear that the PTFE ones should be installed dry, and not with a sleeve. So if you run a sleeve you may want to get the rubber one.

I used the fel pro sleeve. I think it’s Felpro 16250 and their install tool. The tool is listed on the package for the sleeve, so I don’t recall what it is now.

as to why I sleeved it? Well this was how my 100k mile crank looked. You can see the groove, but really can’t feel it. I did a RMS 3k miles ago and it leaked. This time around I inspected closer and saw the groove. Hope the sleeve and new seal work

picture looks way worse than it was. There was nothing you could feel with finger.

 

Last edited: Mar 3, 2021

Reactions: 91GTstroked and Potomus Pete

Mustang5L5

That is…until I whipped out my Bissell

Mod Dude

Feb 18, 2001

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Mar 2, 2021

#18

• Mar 2, 2021

• #18

Oh..and my install tool. Lines up perfectly

 

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SLOWBRA

Founding Member

Oct 30, 2001

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Mar 3, 2021

#19

• Mar 3, 2021

• #19

Specracer said:

Im only a few days from starting it, I hope. The crank was perfect, car only has 8k miles, but used the sleeve anyway.

BTW how are the 00R tanks coming along (yes Im the same guy that has been asking elsewhere, ha ha)?

Click to expand...

If you succesfully resolve the leak please do a write up of exactly what you used/did please. Too many posts with "I think I did this, I believe the part number is this" lol. We need confidence and specifics

No tank updates are expected for many months unfortunately. It's been a mess between COVID delays, NASCAR priorities and now the fabricator has a family member ill. They are legitimate reasons for a delay, but it still sucks.

 

Potomus Pete

I'm still waiting for the fully nude shots

5 Year Member

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Mar 3, 2021

#20

• Mar 3, 2021

• #20

You need to get the skew number off his plumbing device. He will chime in he must of got it at Home Depot. Just for the record. When I changed my clutch I put on a Felpro teflon seal , and the sob leaked right away. Now, besides my clutch slipping and my car smelling with oil on the exhaust. I need to do this sooner, or later.