Rear main seal replacement

[Towrigdually]

I'll be ordering a new clutch here soon and I know my rear main is leaking so I'll be doing them at the same time.  

So with that being said, any tips to taking it out an how to install it? I don't wanna play with an $80 seal and do it 2-3 times before I get it right. 

 

[CUMMINSDIESELPWR]

when i did mine first time (during clutch replacement), i used a small drill bit to start a hole then used self tapping machine screws at 3'oclock and 9'oclock to drive in then pry on. you work the old seal out ensuring you dont score the crank seal face nor the housing seal face.

 

once out, its easy to install.

 

first put the plastic guide sleeve with seal on it, onto the crank face then slide the seal on. place the seal driver ring on top of the seal and evenly work the seal in then with progressive force to drive it evenly home with the seal tool till it doesnt seat further.

 

take your time and do it right the first time, its worth the time.

 

pics below are when i installed during engine rebuild.   so you can see seating reference

 

BTW the seal goes on dry. nothing needed on the outside nor inside of the seal. i didnt use any goop both times and had zero leaks

Edited September 25, 2017 by CUMMINSDIESELPWR

[Dieselfuture]

@CUMMINSDIESELPWR would it be easier to take that back plate off or about the same with patience 

[CUMMINSDIESELPWR]

easier with backplate off for sure.  i didnt have a new gasket for the seal backplate.  but if you have a gasket, take the plate off as its aluminum and easy to score, then you are screwed.

[Towrigdually]

Awesome it won't be as bad as I thought it was going to be then. Thank you for the pics also!

Edited September 26, 2017 by Towrigdually

[Dieselfuture]

5 hours ago, CUMMINSDIESELPWR said:

 then you are screwed.

Then it's back to good ol rtv 

[Cronus577]

Don't get an OEM Cummins rear main seal, did that 2 weeks ago and it didn't seal. Went to O'Riley's and got a felpro seal and the bracket gasket for around $40 and it came with the seal driver to get it flush. The Felpro gasket sealed perfectly, haven't had any issues in 1k miles. Orange is the New Cummins seal and black is the Felpro

[Dieselfuture]

@Cronus577 that's just crazy, maybe some cummins stuff went to China too, who knows. 

[dripley]

I have a Felpro on the rear and it leaks. FWIW I did not install it.

[kzimmer]

I made the mistake of skipping the engine adapter gasket when I did my rear main. Now it sprung a dirty leak. Can't win...

[Dieselfuture]

10 hours ago, kzimmer said:

I made the mistake of skipping the engine adapter gasket when I did my rear main. Now it sprung a dirty leak. Can't win...

Motor honey , no just kidding don't ever use that crap. Someone I know put it in his 350 chevy and ended up throwing a rod through the block. By the time we pulled over there were few holes in oil pan and we could see a fire inside  but he didn't have any gauges hooked up so... who knows if he even had oil pressure, but it was kinda cool to hear a rod break going down a hwy at 70 mph and we lost a little power so he flored it and few more rides broke then it was game over. 

[CUMMINSDIESELPWR]

i paid for genuine cummins when i did all seals gaskets. the front and rear main seals i wanted to do right the first time as i didnt want to tear into it to do it right the second time.  some things are worth the money.