• Welcome to For E Bodies Only !

    We are a community of Plymouth Cuda and Dodge Challenger owners. Join now! Its Free!

Grooved Rear Main Bearing Shell

Steve340

Well-Known Member
Joined
Sep 19, 2016
Messages
894
Reaction score
329
Location
New Zealand
I have been doing some reading and some say fitting the grooved rear main bearing shell cures the rear main seal leaking.
Anyone fitted these bearings? Did they work?
 

Chryco Psycho

Well-Known Member
Joined
Dec 28, 2008
Messages
4,402
Reaction score
2,042
Location
Panama
They can help pull the oil away from the seal for sure so it will not hurt , I generally do not have any difficulty with the rear mains if you are careful assembling them
 

Steve340

Well-Known Member
Joined
Sep 19, 2016
Messages
894
Reaction score
329
Location
New Zealand
OK thanks for the feedback. I think I will try the standard un-grooved bearing and hopefully no leak.
I have purchased some super rear main seal of Mancini so hope it is as good as they say.
 

Chryco Psycho

Well-Known Member
Joined
Dec 28, 2008
Messages
4,402
Reaction score
2,042
Location
Panama
I believe the only size for the brg is std , if the crank has ever been machined there is no undersize brg available anyway
 

Steve340

Well-Known Member
Joined
Sep 19, 2016
Messages
894
Reaction score
329
Location
New Zealand
I read on the net that some people are grooving the bearing with a die grinder. I am concerned about the load on that large rear main.
I think a leak is preferable to a failed main so I think I will not go there.
I have not pulled the engine apart yet but from what I see the rear main setup is similar to a Ford or Chev and they seem OK. The modern Felpro etc main seals seem pretty good.
 

Chryco Psycho

Well-Known Member
Joined
Dec 28, 2008
Messages
4,402
Reaction score
2,042
Location
Panama
the amount of surface area lost with a small vee groove cut in would not affect the life of the brg
 

Steve340

Well-Known Member
Joined
Sep 19, 2016
Messages
894
Reaction score
329
Location
New Zealand
I purchased the Superformance seal but it was no good it leaked.
I pulled the engine and went with common old FELPRO and so far no problems.
Bought it from Rock Auto for $5.20
 

Cudakiller70

Well-Known Member
Joined
Aug 3, 2016
Messages
118
Reaction score
33
Ugh ☹️ I ordered the same seal from Mancini. Thanks for the quick response, I’ll go Napa tomorrow maybe they can get one. Any guesses why? Too soft?
 

Steve340

Well-Known Member
Joined
Sep 19, 2016
Messages
894
Reaction score
329
Location
New Zealand
Yes it did not have the rubber "legs" formed on the seal to locate in the bearing cap and when I pulled the engine apart it had turned in the groove. Use sealer on the back of the new seal anyway - make sure you goo it in real good in both the cap and the block.
There is a machined area in the cap you will see at the join area of the cap. If you do not fill this oil just goes around the seal and you get a leak.
The Felpro cannot turn you will see what I mean.
I also think the seal was not a good fit with regards to the tension of the sealing lip.
 

Cudakiller70

Well-Known Member
Joined
Aug 3, 2016
Messages
118
Reaction score
33
Thanks for info. It’s coming apart tomorrow, I’ll compare seals. Went with the “super seal “ because I really didn’t want to do this twice.....
LOL stock cheap seal probably best! Thanks!
 

Cudakiller70

Well-Known Member
Joined
Aug 3, 2016
Messages
118
Reaction score
33
I wasn’t real sure what to get so I bought a Superformance seal from Mancini and a stock type from Fel-pro. Superformance on the left. I kind of like the stock (on the right) because it has a solid type lip. Superformance lip seems a little limp or soft.
36D3C819-BBAE-430C-921C-5801EBC97CBD.jpeg
E4FB9D25-ABA8-4204-8FAE-0ACAFFFBCA81.jpeg
7A1D4167-3EC8-4A25-91FD-215E7ED568D4.jpeg
B04430CC-5782-4CD1-81D3-ADF5B6EB2CE4.jpeg
 

Steve340

Well-Known Member
Joined
Sep 19, 2016
Messages
894
Reaction score
329
Location
New Zealand
Yeah I know what you mean. That Superformance lip appears to not have enough lip tension on the crankshaft as mentioned in my earlier post. Mine would start to drip oil after about 10 minutes of running.
Superformance gets a big thumbs up from Mancini on their website but I am no fan.
Because these engines had a rope seal the machining tolerances around that seal area could be pretty loose. In short the rope seal was not bothered by a few thou here and there or a bit of misalignment. A rubber seal is not so forgiving.
Do a trial assembly of the cap with no seal in place and check the seal halves line up and make sure the seal has a bit of tension in the groove. Larry Shepard mentions in his book the seals can turn (mine did) this lead me to the conclusion my block recess for the seal is on the big side of measurement.
 

Cudakiller70

Well-Known Member
Joined
Aug 3, 2016
Messages
118
Reaction score
33
Yup! You saved me a lot of aggravation.
Thanks again for the quick response!

Yeah I know what you mean. That Superformance lip appears to not have enough lip tension on the crankshaft as mentioned in my earlier post. Mine would start to drip oil after about 10 minutes of running.
Superformance gets a big thumbs up from Mancini on their website but I am no fan.
Because these engines had a rope seal the machining tolerances around that seal area could be pretty loose. In short the rope seal was not bothered by a few thou here and there or a bit of misalignment. A rubber seal is not so forgiving.
Do a trial assembly of the cap with no seal in place and check the seal halves line up and make sure the seal has a bit of tension in the groove. Larry Shepard mentions in his book the seals can turn (mine did) this lead me to the conclusion my block recess for the seal is on the big side of measurement.
 
Back
Top