New Rear Main seal Install


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Feb 24, 2021
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Good Day All
Just returned from the machine shop (Harts) with all the goodies to rebuild the Party Barge's 383. One question; For my own piece of mind, do I have the rear main seal installed in the correctly? Installation instructions call for the large lip to face the front of the motor. It just doesn't look correct.
Also, I see on you tube that some install the 2 piece so that the part line does not line up with the block. Basically the seal sits 3/8 inch higher on one side wile sitting the same amount lower on the other side. I don't know why unless its for oil control. Thoughts?
Unfortunately, every pic I take won't upload (error message states that the uploaded image is too big). So, Does anyone have pic of what way the seal sits in the block?
Thanks to all who respond.
As i see it, the lip forms sort of a cup between the housing and the crankshaft. With the lip facing the front of the engine that cup is in the inside of the engine and oil will push the lip onto the crankshaft. If you flip it over the oil will push the lip towards the housing causing it to leak. I hope that makes sense
Good Afternoon

No I phone (Cannon Sure Shot). Anyway, played with camera and I think this pic shows my question. Is this seal installed the correct way?
Again, Thanks to all who respond.
That’s right.
Good Morning All
It's 2:41 A.M. Snowed all night. I'm on the computer looking for 'How-to-Install' tips and found this: felpro-rear-main-seal-installation-bulletin.pdf
Good Stuff and it answered my question.
the fit on the factory aluminum seal retainer isnt the greatest which doesnt really matter with a rope seal but with a rubber one there's a chance the 2 ends of the lips won't line up if installed flush with the block surface cause theres a chance the retainer groove may wind up slightly ahead or behind the one in the block... by offsetting them they will both end in the same groove and hopefully won't can truly drive yourself crazy researching how to install a 440 seal and all the problems and cures involved...good luck
Lip is correct direction. Do not have the seal ends and the block/retainer lined up. 1/4"-3/8" is good any more and it may not want to slip into the piece of the groove. Someone over on FBBO mentioned putting the seal in at 90°, which would put the seam at 12&6 o'clock, bad idea to put seam on bottom where oil collects.
RTV the side seals in and then run a bead up the back.