440 rear main seal replacement.

[67charger440]

I know approximately 6 million threads have been created on the topic, however, I would like some fresh input. I got a 440 that has a pretty solid engine oil leak coming from the bell housing dust cover. (Yes I’ve checked valve covers and oil sending unit). I’ve also read on the previous threads that this is a common problem with the 440. Much like trying to seal a 727 transmission pan. What is the latest and greatest rear main seal to purchase that y’all would recommend? Also I plan to pull the motor. Yes I know it can be done in the vehicle but I got a engine hoist that looks lonely. Thanks for all the input. Much appreciated.

 

[zyzzyx]

I'm crossing my fingers and just put a Viton two-piece in my engine. The joint lines should be staggered from the
housing by about 3/4" and bedded in RTV. Hopefully this works! The crank has shallow slash marks in it to direct
the oil back towards the crankcase, so I hope everything works as it should. Good luck!

 

[beanhead]

Factory retainer and FelPro flouroelastomer/Viton seal. If you want to, you can use one of the billet aluminum retainers but the factory piece works fine (and doesn't cost $100) and some have reported they've had to shave a tad off the mounting surfaces of the billet units.
Getting them to seal properly is all in the installation..
I like your plan to do it with the engine out, that way you can test it before reinstalling (hang the block ***-down and pour enough oil in to cover the seal.) If it's gonna leak, it will leak on the hoist instead of in the car. I like to use a thin synthetic for testing purposes too, that runny crap will show any leaks pretty quickly..

 

[70bigblockdodge]

Stagger the ends away from retainer/block. Very clean and dry side grooves filled with small bead RTV before assembly and then squeeze a full bead RTV on the taper to the block area once bolted in place.

 

[diesel_lv]

Just did mine a month ago. My engine builder told me "I know what I'm doing" when I told him there was a specific way to install main seal. Unfortunately, he did not know. Yes, there are many ways. Here's how I did mine and no leaks so far. Used the Felpro kit with viton side seals. I actually placed the crank seals 50/50 in and out so the seam is running at top and bottom. I got some extra long bolts and cut the heads off then cut a slot so I could use a screw driver to put in and take out. These studs act as a guide. A dab of "Right Stuff" on the cap mating surface and then gently slide cap on. You should feel it center itself. I practiced this about 5 times to get the feel before adding sealer and actual install. Then a dab of Right Stuff on end of side seal and slide in. It should sit flush. Then I backed out one guide and installed factory bolt then the other. Then torqued it down. No leaks in a month and I run 5-30 synthetic.

 

[gkent]

"I know what I'm doing"

A flag goes up the moment I hear that. I can say with high certainty that nine times out of ten that I've heard that they screwed it up.

 

[diesel_lv]

A flag goes up the moment I hear that. I can say with high certainty that nine times out of ten that I've heard that they screwed it up.

He "had" a great reputation. Built my 4.6 DOHC turbo engine for my jet boat and it was/is great. "But...." after being on Street Outlaws, he got a bit high on himself and from what I've heard after my 383/496 build, his quality has gone downhill.

 

[Darter6]

Do what I did,,Just sell the car !

 

[451Mopar]

Check the seal retainer oil pan holes too.
Had an engine where someone put the wrong size oil pan bolts in the retainer, likely because they stripped it out, and also broke through the bottom of the retainer bolt holes. Reminds me of my old '86 truck when I bough it, the torque converter bolts were wrong thread and too long. Pulled a flexplate to converter bolt and all the trans fluid came out!

 

[1967coronet]

Make sure you have a working pcv system.
Crank case pressure can cause leaks.
Not saying you dont need a rear main seal replacement. Just that a working pcv system will help you have a successful outcome.

 

[zyzzyx]

Another thing that is important is piston ring seal. Make sure your rings are spaced
according to the manufacturer's instructions. Cylinder finish is important too. It all
adds up!

 

[Carcinogen]

At 16:30 Nick shows his method.

 

[zyzzyx]

So, he never showed if it leaked or not! I guess not, but who knows. I just wonder how he could put an engine together
with the wrong spring pressures and put it out there on YouTube? 5500 and breaking up?

 

[451Mopar]

I just wonder how he could put an engine together
with the wrong spring pressures and put it out there on YouTube? 5500 and breaking up?

Not sure, but sometimes the engine owner wants to try running with springs they already have?
I'm sure if there was a question on valve spring pressure that they would be keeping an eye on the dyno as RPM climb.
Sometimes you use what you have as a baseline too. There is many combinations that don't have a "recommended" valve spring, and you have to experiment.

 

[diesel_lv]

So, he never showed if it leaked or not! I guess not, but who knows. I just wonder how he could put an engine together
with the wrong spring pressures and put it out there on YouTube? 5500 and breaking up?

If I'm not mistaken, I think I watched a video after that one awhile ago where he said it did end up leaking.

 

[dvw]

For me I never have offset the seal. Not that it's a bad idea. Never had need to do so. If you bolt the retainer in with no seal you will probably see that the the sides of the retainer don't appear centered in the block. For this reason I fill the sides with RTV, (I prefer Ultra Grey). You can fill the area at the back of the retainer and use a putty knife to smooth it. Also a little anerobic sealer between the retainer and block will stop any weepage. It is imperative that the seal in the cap surrounds the crank journal centered. How do we do this? Open the holes in the retainer slightly (1/32"). Now the seal will center the retainer, not the bolts. Are the oil pan bolt holes are cracked thru from using bolts that were to long? Two easy fixes. White Teflon sealer on the bolts. Or install studs with lock-tite. Fill the retainer bolt holes with RTV after installing the retainer. Not all oil pans cover the hole completely. Haven't had any rear main leaks in 30+ years of building motors. Also for what it's worth my Sons small block was leaking only under boost. It turned out the rear cam plug was cracked. We had a box of 10 Dorman plugs. Everyone in the box was cracked. Never assume.
Doug

 

[zyzzyx]

I've heard other members stating that the bore of the retainer is not concentric with the crankshaft on
some engines. Someone out there makes a seal that only has one joint line so you can slip it in the retainer
and "fish" it around. If I had the time, I'd design a fool proof seal!

 

[dvw]

Just put the rear main seal in my receptor today. Tried offsetting the seal. Found it easier to start the seal in the block against the crank. Then lower the retainer down on to it. Filled the side grooves with rrv 1st. A little anaerobic on the retainer and bolt it down. Then fill the outside 45 degree recesses and the bolt holes. As you can see in the last pic the rtv makes its way inside the edge of the retainer. No leaks here.
Doug

 

[4406bbl]

You need to make sure the seal ends are lined up and that the seal actually touches the crank, factory machining it pretty bad as the rope seal made it not important. This block needs the seal retainer moved to the right about .005. I stamp the feeler gage size on the retainer for the next guy or easy in car changes. The other 2 figures on the back of retainer are how far in the retainer is from the rear of the block. This one is close, some are way worse and by the time you move it over enough the side seal does not touch.

 

[4406bbl]

Feeler goes here, torque one up with no crank and look sometime, then put the crank in and see if the seal touches all the way around.