REO 331 gasser rear main seal. Trick for replacing it?

[JH1]

The designers of the REO 331 Gold Comet gas engine in early deuces must have stayed up late, trying to make the rear main seal as hard to replace as possible. Normally, when you remove a clutch and look at the rear main seal on an engine, all you have to do is pop it out and cram a new one in it's place. Not so on the REO, as far as I can tell. Looks like you have to drop the pan and potentially remove the bell housing, which means you have to either yank the engine or support it otherwise. There has to be a
trick for this.Anyone know what it is? I have some manuals and they pull the engine and put it on a rotary stand, then pick it apart like a buzzard until it's bare. I would rather just change the rear main seal with the engine still in the truck. Ideas?Jim

 

[onegmjack]

First of all I have never done one, so could be wrong. Looks like the seal is in a stamped steel plate that bolts to the engine. The plate has to come off engine then the seal removed. The plate has a lip looking from the rear that keeps the seal from just being pulled out. Maybe someone that has replaced the seal will enliten us.

 

[73m819]

The 6602 gasser in the early 5ts has the same design, when I had the trans out, I pulled the clutch and flywheel, thinking I would find the rear main, WRONG, the bell housing/rear engine support needs to go. It looks like you would have to pull the motor to get down to the rear main because of space there seem NO WAY to pull the bell housing/rear engine support, so with the above said, the 6602s rear main STILL leaks. This design is a MILITARY mod to the civi engine, why ?????

 

[gringeltaube]

Gold Comet, rear main seal replacement: no tricks... and yes, it's a PITA, because only the 4 upper bolts of the total 9 screws holding the (stamped)seal retainer assy #8331248 are bolted directly to the block. The lower 5 bolts go through the retainer #7521931, from front-to-rear and are only accessible after dropping down the oil pan.
The bell housing doesn't have to be removed.


G.

 

[JH1]

Ok. Do we have to remove the pan or just loosen it so as to pull the aluminum plate backward, clear of the engine? Appears to be a couple of screws affixing the aluminum plate upward to the block. I think we can access them from just behind the pan. Thanks for the help, guys.

 

[tigger]

This design is a MILITARY mod to the civi engine, why ?????

Because they can!!!!!!!!!

 

[onegmjack]

The seal may have been coming out, so they caged it, to hold it in.

 

[JH1]

OA331 gasser Rear Main Seal.There HAS to be a trick to this.

Working on a deuce crane truck M108 with the OA331 gasser (Gold Comet). Procured a NOS rear main seal. Now, to get the old one out. It appears that the engine bell housing(which also supports the engine by two external mounts to the frame) has to be removed in order to get the aluminum carrier plate out, so I can unbolt the actual seal. The manual shows the entire engine out on a convenient stand in the shop, with a wrench removing bits at will.

The next idea is to support the rear of the engine from above somehow and then remove the bell housing. This is nuts! What's the trick to this??

 

[gringeltaube]

Only two weeks ago.....
http://www.steelsoldiers.com/showth...-gasser-rear-main-seal-Trick-for-replacing-it


G.

 

[tigger]

you answered your own question!!

 

[JH1]

Not really. There appears to be yet another solution. Looks like I could drop the pan and access the Allen head bolts that affix the stamped steel bearing holder to the aluminum plate. The aluminum plate could stay where it is. It can't go rearward because of the bell housing. But if I can unbolt the actual seal carrier, I don't need to move the aluminum plate at all. At least that's what it looks like so far. I'll report back. Btw, we had to literally chisel the pilot bearing out, after breaking a HF pilot bearing tool. I guess 60 years in one place made the bushing kinda stuck.

 

[gringeltaube]

................. But if I can unbolt the actual seal carrier, I don't need to move the aluminum plate at all.......

That's why I said in that other thread that you have to drop the pan to get access to the lower 5 bolts, from a total of 9 holding the seal retainer in place.



G.

 

[Warthog]

Merged threads. No need to have TWO threads asking the exact same question.