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Installing rear main seal - RB block

440beep

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So my RB block is leaking oil from the back of the motor, thinking its the RMS. We installed a Fel-Pro RMS last week which didn't help, its leaking worse now (but could be the ligher weight oil also, or seal installed wrong way). So I ordered the below kit from Mancini Racing and also the Vinton seals from 440Source which I'm guessing I can only use the split seals since the below piece has 2 rubber side seals per side. Seems to be a very nice piece.

My question is this, when installing it, are you supposed to oil up ALL the seals then install quickly since the seals expand? Do you just use motor oil, or can you use grease or assembly lube? However, I've seen some instructions that say to put RTV sealant on the sides. Do you do both? Oil the seals then put RTV sealant on? Or does the RTV go on after the retainer is installed in the block and the RTV covers up the seam between the block and retainer?

We are going to install these new seals/pieces this weekend and want to get it right this time.


chucker54_2233_38286304
 
use a light amount of eng oil on the seals before assembly so they dont get damaged with a dry install.the rtv goes on the mating surfaces and only a very small dab,just to help seal the ends of the seals.
 
Hell if I know. I've always seen both like you say. And seen people completely eliminate the side seals in favor of RTV...and it NOT leak.
 
Yea, I'm stumped too. With the new Mancini retainer the side seals are a tight fit, so I'm assuming don't oil the seals, but put a dab of oil in the side grooves and slide the seals in and hope they don't swell up immediately. Read the instructions for the Mancini retainer, and I'm still a lil stumped at how to install the side seals. You're supposed to do something with the long silver bolts while getting the side seals in, then once in, remove the silver bolts(??). :icon_eyes:
 
I've used four of these Mancini main seal systems. Install the side seals buy putting them in the two small holes in the bottom of the cap on each side. Fold them up around the sides and press them into the sides of the cap. Try not to stretch them very much getting them in the side slots. Put a dab of silicone around the bolt holes on the bottom of the cap, it won't take much. Lightly grease the sides of the block, install the supplied studs into the block to guide the cap into place and push the cap into place. Remove the studs, install and torque the supplied bolts. Trim the excess side seal off. There is always some side seal that will extend out farther as you push the cap into place, this is normal when installing the Mancini main seal cap. By the by, you don't have to get in a big hurry, those seals aren't gunna swell as you attempt this project.
 
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