Best way to install the rear main seal on a 5.9 magnum

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maca

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Hey guys over the years I've installed several rear main seals on my magnum engines and some have leaked which is annoying on a brand new engine. I used to just put Loctite in the groove and then press the seal in but this has leaked several times for me.
The last one I did I placed a generous amount of gasket sealant in the groove and then press the seal in and it didn't leak. Don't know if I got lucky or this is the correct way to do it.
Could someone please confirm the best way they have found.
I have noticed in the kit there is a little white funny shaped piece of plastic. Not sure if this is to be used to spread the sealant.
 
I also use sealant. Ever a problem. Never used Loctite.
 
I just push the seals in dry. Smear some oil on the lip of the seal. Set the crank in and put a light coat of RTV on the block to main cap surface. I also put a small amount on the edge of the seal where the seam will be.
 
maca said:
Hey guys over the years I've installed several rear main seals on my magnum engines and some have leaked which is annoying on a brand new engine. I used to just put Loctite in the groove and then press the seal in but this has leaked several times for me.
The last one I did I placed a generous amount of gasket sealant in the groove and then press the seal in and it didn't leak. Don't know if I got lucky or this is the correct way to do it.
Could someone please confirm the best way they have found.
I have noticed in the kit there is a little white funny shaped piece of plastic. Not sure if this is to be used to spread the sealant.
Click to expand...

The little plastic piece is to be used as a type of shoe horn for putting the seal in so the edges don't get cut. (I don't use it)
Rear main seals never used to come with them, so...
I just oil up the seal and slide it into place only using a dab of RTV on the ends where the two halves meet.
 
TrailBeast said:
The little plastic piece is to be used as a type of shoe horn for putting the seal in so the edges don't get cut. (I don't use it)
Rear main seals never used to come with them, so...
I just oil up the seal and slide it into place only using a dab of RTV on the ends where the two halves meet.
Click to expand...
So no sealant at all on the magnum seal Only on the ends?
 
maca said:
So no sealant at all on the magnum seal Only on the ends?
Click to expand...

Only on the ends once the seal halves are in, and a thin film where the main cap meets the block.
That's the way I do it, but you you know how opinions are.:D
 
I've never used sealer on any part of the rear seal or cap.
It goes in dry, - lube only the lip.
The plastic piece is used when installing the seal with the crank in place. ie, in car.
 
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