Rear main seal, my error

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NAM VET
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Rear main seal, my error

Post by NAM VET »

Not easy to post on a forum one's dumb mistakes. If you have followed my saga about trying to find and install a rear main seal, and the costs so far to me, other guys with more experience than me have likely wondered "what could be so hard about all this." There are I think three types of RMS's, the "rope" ones, the inner one, and then the six bolt plate that goes on the outside, my motor has the drilled holes for the six hole plate.

I just could not get the inner rubber seal to fit in the recess, so decided to order several of the plate seals. Today I dropped by my machine shop to pick up the flash drive with the pictures he took of my motor as he dismantled it. In reviewing them, I was struck by how obvious it is what my problem and misunderstanding has been. Of course, the inner seal does not fit down into the groove, it sits partly in and partly out. So removed my crank, being glad I have not yet put the pistons in, cleaned everything, and then easily put the inner two half circle RMS in properly, and reinstalled the crank.

Here is the picture that made my difficulty so clear:
[URL=http://s663.photobucket.com/user/h ... .jpg[/img][/url]

And here is my RMS now correctly installed:
[URL=http://s663.photobucket.com/user/h ... .jpg[/img][/url]

I decided to go ahead and illustrate my error, because perhaps some builder in the future may have the same quandary as I. Moving forward once again.

NV
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HingsingM37
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Re: Rear main seal, my error

Post by HingsingM37 »

No harm, no foul. It is easy for anybody to make that assumption if it is their first time in one of these old classics. :) Thanks for sharing.
David
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1958 M37B1
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just me
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Re: Rear main seal, my error

Post by just me »

I see smuck in the edges of the bearing cap seat!
"It may be ugly, but at least it is slow!"
NAM VET
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Re: Rear main seal, my error

Post by NAM VET »

yes, but I took the picture of my cap before i thoroughly cleaned all the corners and crevices of the cap and seat with a fine blade. Scrubbed with lacquer thinner, dry, with a non-lint cloth, then a tiny bit of Halomar non-hardening sealant here and there.

I am trying to follow all the suggestions I find here and on on-line tutorials. Just put the pistons in with my adjustable bore specific compressor. Crank turns, end play within spec.

back to work now.

NV
Cal_Gary
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Re: Rear main seal, my error

Post by Cal_Gary »

Well you motivated me to get after mine today-I spent about 4 hours dropping the oil pan, cleaning it out and removing the old gasket, then dropped the main bearing cap and replaced my rear main seal. I first did the job over 10 years ago, and those seals were hard as rocks! Anyway, got all of it completed, to include using anaerobic sealer on all of the contact points and changed the oil while I was at it. Satisfying but tiring doing it in the vehicle.
Gary
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1954 M37 W/W
MVPA Correspondent #28500
NAM VET
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Re: Rear main seal, my error

Post by NAM VET »

15 years ago, I drove the 200 miles down to Charleston for a conference, and about 2 AM, my right arm hurt so bad I had to drive with one hand to a nearby ER, where the nurse told me what was wrong before the MD even came in to examine me, that I had a pinched cervical nerve at C7 in my neck vertebrae and shot me full of pain med. I then drove the 200 miles home using only my left arm and soon had a steel plate put in my neck as part of a cervical fusion. So it is impossible to turn my head very far to each side, and even more so to bend my head back or very far down. Not too much of an inconvenience in life, but it makes working under a vehicle more difficult, especially since I am so prone to spatial disorientation (ie, motion sickness). If I have to get on my creeper for very long, I take a Bonine anti-motion sickness pill first. How did you manage to spin your old seal out and spin the new one in? And hold your sump pan up while you started your fasteners? Congrats on your own under-the-truck repair! Try driving one of these 200 miles using only your left hand, not easy.
[URL=http://s663.photobucket.com/user/h ... .jpg[/img][/url]
Cal_Gary
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Re: Rear main seal, my error

Post by Cal_Gary »

The top half of the seal can be rotated around the crank-use a blunt screwdriver to get it started then grab the protrusion with a pair of needle-nose pliers and pull it out. Slather up the new top half and insert it through by hand since it's so pliable and I used liberal doses of anaerobic sealer on all the potential leak areas. For the oil pan I aligned it then used a 2x4 under the reservoir end to add some lift support while using my off hand to lift the front and start a couple of bolts, then moved to the rear and started a couple more. One of the pan gaskets tried to bail out even though I glued it to the pan with some sealer so I had to realign it then hand-started all the bolts then worked my way back and forth snugging the oil pan bolts.

I now need to pick up another oil filter-I always like to have one on the shelf....
Gary
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1954 M37 W/W
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