i recently found one of my motors was leaking oil at the rear Main Seal. very slightly, but having never had this problem it got my attention.

i buy many of my internals from Atkins and a while ago the color of the rear main seal switched from orange to a deep red.

as you can see from the pictures more than the color changed.

the new seal has a 5 mm contact surface and the old seal has 10!

needless to say CPR motors will come w orange rear main seals going forward. Atkins has indicated they will be happy to ship the orange seal. i do like lots of Atkins items but not the "new" seals.

 

The new seals are RX-8. I don't like them either.

 

Common knowledge for experienced engine builders. Brown is N3H1-10-5080 04+ Renesis. Orange is 1668-10-556A everything prior.

 

I just bought the red one in september and installed it. No leaks yet, but i kinda feel ripped off after seeing this. Oh well i guess.

 

The seal isnt going to be pushed out or spun, nothing really to be concerned about.

 

it looks like the surface touching the shaft is about the same thickness anyways, if not the red one is thicker.

 

this. the outside is stationary and having done 100+ real main seal jobs.. it never leaks from the outside unless the seal gets pushed out, and that is usually a clogged PCV.

 

the seal was leaking from the outer contact surface on two motors. i have never had an orange seal leak in such a manner in over 100 motors. i can also state that the seal was installed properly.

bottom line for me is 10 mm contact V 5.

i will take 10.

 

I'm not a experience engine builder but what been working is using RTV on the outer part of the seal instead of oil to help the seal slide into place. Just a small amount will do. Maybe this is a common thing to do but did not see it mentioned.

 

IMO RTV not needed. Use the proper Mazda part for the 13B-REW engine and there won't be an issue.

 

yo can tell by the way it goes in the stat gear . retails rx8 $10.39 prior $13.49

sucks to do all that work just for saving $3.10

 

They're the same price on mazdatrix.

 

On my RX-8 I installed the red seal (of course because it's an RX-8) when I replaced my clutch and installed a racing beat flywheel and CW. I asked beforehand about proper installation with the motor assembled and in the car (as I've only replaced the seal on stat gears prior to installing on the iron). My post got flamed with this type of info saying the Atkins seals are garbage and always leak no matter what. I contacted Atkins and asked if they've experienced any issues and they said almost never. I then asked about proper installation and here are the instructions I was given:

1: Ensure the CW or flywheel surface is clean and smooth. polish with steel wool until desired finish is achieved. Both Atkins and Racing Beat recommended this)

2: Clean the inner part of the stat gear where the outer part of the seal sits thoroughly and ensure it's clean and dry before install (I did this with acetone)

3: When installing the seal, ensure that it goes in evenly and all the way flat to the bottom. (I did this with a plastic cup and mallet)

4: add a thin coating of lubricant to the inner riding surface of the seal. (I used petroleum jelly for this)

5: Install CW or flywheel.

So far I have about 5,500 miles on the new seal and no leaks at all. I think that the people having issues just aren't installing them correctly