Rear main seal leak?

[PurpleBeeper]

If I do need a new rear seal, what brand seal and sealant does everyone recommend?

I've had good luck with the Felpro seals, but I see Cranky prefers the "rope" type. Don't forget to put a little dab of RTV silicone on the lower corners of the rear main seal retainer at the seams and where the two halves of the rear main seal join each other. I've heard that can leak too.

Felpro type - they go in one direction & it matters (can't remember lip forward or lip backwards?)

Rope type - make sure to cut off the little bit extra "rope" with a sharp razor blade. These probably seal better, but you need one of those "Chinese finger lock" tools to pull in the top half of the seal over the crankshaft.

 

[Fran Blacker]

Somebody makes a "one piece" seal it only has one opening. I misplaced who made it, dam.

 

[Fran Blacker]

Try this Fastfish auto parts.

http://www.fastfishautoparts.com/Performance-Engine-Seals.html

 

[Mike67]

Tried googling a one piece and got nadda, but I did find a dual lip seal...??? Which is a one piece that you make one cut on...
http://www.fastfishautoparts.com/Performance-Engine-Seals.html

 

[Mike67]

Beat me to it Fran!

 

[Fran Blacker]

Great minds think alike!

I'll be waiting for the comments.

 

[moparnation74]

Personally, doing a rope seal with the crank installed would be a royal PITA.....

One big mistake people make with the seals is not allowing the thin film of RTV to set up appropriately. When it is not set it will blow oil through...They will get everything installed and fire it up! I let them sit for two days prior running the motor...

 

[Cranky]

The Fast Fish seal is 72 bucks!!

 

[Mike67]

If it works it would be worth it to me to keep from dropping a pan, oil, filter, pan gasket and headache...Curious if anyone had any first hand expierence with it???

 

[Fran Blacker]

The Fast Fish seal is 72 bucks!!

Yes it's a stiff price. Agree with that. Have a rubber seal in one motor and a rope seal in other.
I like the rope seal better, but you gotta cut it right.

 

[superbird77]

Tried googling a one piece and got nadda, but I did find a dual lip seal...??? Which is a one piece that you make one cut on...
http://www.fastfishautoparts.com/Performance-Engine-Seals.html

Thank you, I googled it and found the same. That seal has more controversy than a Hillary Clinton email trial.

 

[Fran Blacker]

Thank you, I googled it and found the same. That seal has more controversy than a Hillary Clinton email trial.

Unfortunately she didn't go to trial! Guilty Guilty Guilty on all counts!

Edited my misspell of trial from originally posted trail, wish Hillary would hit that or Billy boy.

 

[Mike67]

Lol!! Thats funny...and wishful thinking!

 

[Fran Blacker]

Call the spelling police! Post 32 Excuse eye doc screwed with my eyes today.

 

[Mebsuta]

Just tore down a rebuilt 383 that had the rope seal in it. The whole engine was one big greasy mess but the back of the block was dry as a bone. And I don't see how a lip seal can last with the factory knurling on the crank......

Going back to the rope seal if I ever do another one.

 

[Dibbons]

What was wrong with the rope seals in the first place? I thought it was horsepower lost, not leaks.

 

[69Bee]

Everyone has covered the obvious, but the only thing not mentioned is that one half (or both) could be in backwards. If the lip of the seal does NOT point in (towards motor), it WILL leak. It is possible with the aluminum seal retainer to have it correct, but realize you have the retainer in backwards, and flip it around without doing the same for the seal. Block side good, retainer side backwards. Don't ask me how I know...

 

[Cranky]

Yeah, a rope seal does rob a bit of power but how much? Anyone ever do a dyno test with rope vs lip and saw a difference? When racing and every ounce counts, yeah, go with the lip seal. It strikes me odd when someone will build an engine/trans and uses all the tricks to produce horsepower and reduce parasitic loss but the car itself is fat as a pig with all kinds of sound deadening products and accessories like AC, PS and the list goes on without any regard to the stress a heavy car places on the drive line. I've never worried about a rope seal leaking but always did when using a lip seal. Maybe I just wasn't setting up the lip right but now there seems to be many more products out there to make the job go better.

 

[5.7 hemi]

Question..... isn't the rope seal only for knurled cranks? The 1 piece seal is pricey, for use on non knurled cranks?, and you only have 1 possible spot for it to leak.

 

[Cranky]

Question..... isn't the rope seal only for knurled cranks? The 1 piece seal is pricey, for use on non knurled cranks?, and you only have 1 possible spot for it to leak.

That's what I always thought too until this thread was started and this link was posted....
http://www.hughesengines.com/Upload...in_Seal_Installation_InstructionsJune2006.pdf