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440 Rear Main Seal - Cap Side Seal Adhesive?

PurpleBeeper

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I've read the sticky & links.

I've got a 440 and am replacing the rear main seal with a viton main seal & the silicone side seals in a Hughes "cap". As many of you know, the silicone "cap side seals" really want to slide out while you're pushing the cap up/in (engine in car). Is there an adhesive I can use to hold the silicone side seals in place better while I install the cap? I do have a small amount of assembly lube on the outside of the side seals, but they keep wanting to pop out as I slide the cap in. IDEAS? Thank you
 
I used a small screwdriver to push them in a little at a time. And I moved the retainer up and down, as I worked them in. Took awhile, but finally got them all the way down, and flush with the pan rail. After installing the retainer bolts, I cleaned it and applied max oil resistant silicone to the outside of retainer, where it meets the block. And a thin coat at the pan rail. Hasn't leaked at all! I think the factory type hard side seals are easier to get in there. Those have worked well too, when siliconing the outside edge.
 
They may appear to slide out when in fact they are stretching to fit the space. You can pull them down below the mating surface a bit then start fitting the retainer. The little bit will basically catch and drag the seal in as you install it. When the seals contact the mating surface they'll push up into place.

The alternative is to throw those away, load up the slots with sealant, install the retainer then stuff a length of pipecleaner down each slot.
 
I kept moving my cap up and down a little at a time. I had a light coating of oil on them. It took a couple tries but they eventually seated flush. I would only pull the cap up even with the seal then push it all down while pressing the seal in with my index fingers.
 
On the aftermarket retainers that fit the side seals pretty tight, I start with the seals a bit below the cap and work the cap up and down to get them all the way down.
I just did one with the stock retainer which seems to fit a bit looser, and I used a little bit of Indian Head Shellac to glue the side seals to the caps.
 
Some guys also swear by not using them, and just filling the grooves with sealer. I did mine this way, ultra-gray on the sides and bottom of the retainer but I have a Mancini piece which has two very small grooves on each side instead of the factory style one big groove...however, the jury is still out as mine hasn't been tested yet. I installed the new seal monday and want to let it get good and cured before letting oil touch it. Probably be another week...
 
I never use the side seals, just fill the groove with RTV and shove a damp pipe cleaner into the groove after the cap is installed. RTV cures by moisture.
 
I know some of the Fel-Pro rear main seal kits just came with a tube if RTV and the pipe cleaner as mentioned above
 
Try installing them oil free like the instructions state. Oil free grooves too.
Some instructions say to soak them in paint thinner, or mineral spirits first to make them swell.
Well that didn't work with the factory type! Fel pro I think. They were too big after that! The hot oil is supposed to make them swell and seal I think. The 440 source ones I tried were pliable, (neoprene?) and were hard to get in. No instructions. But it seems to be sealing well with them, and gray silicone on the outside.
 
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