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318 rear main and other ?s LONG winded

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1930

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Brandon Florida
I know the internet is full of comments but anyway I plan to change the rear main seal next couple of days in my 79 Adventurer 318 2WD.

Ive got the Fel-Pro gasket, I asked around it it seemed that was my only option. Id have preferred a one piece re-usable but none avail that I could find.

Ive also got the Fel-Pro 2 piece seal. I guess I havent handled many rear main seals, I did not expect it to be rigid the way it is, I assumed it was rubber and flexible throughout.

I plan to do it in the truck, I have a lift and tools wont be an issue as far as I know.

I plan to loosen motor mounts at the crossmember I guess, raise engine using my cherrypicker and then put some 4by4s somewhere underneath to keep it raised.

( assuming I have to do all this to get pan off )

Im assuming the engine is basically untouched, truck came out of New Mekiko, fairly rust free and pretty much original.

Id like to say that the truck was well cared for with proper oil changes ect. Ive had quite a few issues with the truck though since owning it and Im trying to convince myself that its cause the truck sat in someones garage up on blocks in a temp. controlled environment and just wasnt used enough :)

Reality is that maybe it wasnt and although the miles are fairly low ( 70 sumpthin maybe ) it may be kinda wore down.

Im wondering if since Im under there should I change out bearings, no noise ( other than a lifter that occasionaly wont pump up ) Changing bearings is cheap and easy so maybe I should just get it done.

It burns oil upon startup at least, Ive always assumed that the valve seals just are dryrotted and that would be the cause of that. Im pretty sure Ive dealt with that in the past as well and that is an easy fix.

Anyway any comments on rear main replacement, bearings change and anything else would be appreciated, Thanks


Do I need to purchase something called a Sneaky Pete?
 
Im building a 340 for the truck, engine is having machine work done now. I dont want to maybe get too crazy with spending money on this 318 but I VERY much enjoy the experiences of learning new things, I learn new things by doing them and so I wouldnt mind doing some other work if it made sense.

I gotta change the rear main and oil pan, it is really bad and Im tired of cleaning the floor in my shop.

Im a bodyman of over 30 years, Im not a mechanic but can fix anything.
 
I don't think I'd mess with the bearings unless you've got really low oil pressure - you have checked that haven't you? If not, get a mechanical gage on there and check it both cold and at operating temp before you open things up. I've done what you're about to and while it's not much fun it's not a horrible job. You may have to loosen the mains a bit to allow the crank to sag down and allow the main seal to come out/be reinstalled, I did on mine.
 
It would have been nice to know that I didnt have to do anything to the engine as far as lifting it, Im glad I trusted my instincts and just dropped the arm that I show in the picture, oil pan had more than enough room to slide out. Ive got maybe an hour into it so far and have removed the starter ( may not of even had to do that technically ) and dust cover and oil pan.

Ive removed 4 out of 5 main bearings, loosened the 5th cap so that its off the seat, not sure what Im expecting, its not gonna drop much in the front cause of at least the chain, not gonna drop much in the rear cause of converter.

Not having any luck still though removing that seal, have tapped with a screwdriver both ends, dosent seem to be moving, only absorbing the screwdriver itself.

Trying to pull on it with the screws Ive put up in there and again its still not moving.

I figured it would be best to get some suggestions.

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Im gonna loosen the converter in the A.M Thats gotta give me something to work with if that crank drops down. Thanks
 
When I did mine I got enough sag just loosening the bearings. Mine is a 4 speed though, but that shouldn't change things except to make it easier for you to loosen up the converter than if I'd tried to undo the clutch.... Good luck with it.
 
Turned out to be a ropeseal, no way it was coming out like I was trying, unbolting converter still dosent allow converter to go back far enough to disengage crank, have to loosen all trans bolts, slide back trans, drop the crank and go from there.

Wont do it again in the vehicle. Too much to go wrong and I dont like hoping for the best and crossing my fingers on stuff.
 
Oh man, sounds like "if it can go wrong, it will - at the worst possible moment". Don't know of an easy way out on that one. They promise a sneaky pete will work on them but I'm not sure I really believe it.
 
To remove the rope seal the screw in one side should do it, use some vice grips on the screw for leverage to pull down with. The tool that is made for it is a long screw with a loop on the end. You should be able to replace it with a rubber seal.
Make sure you have the lip going the right way, towards the crank not the flywheel. Good luck:)
 
Thanks for asking, it went back together fine, I did the valve cover gaskets at the same time, had to do them twice cause the first set ( fel-pro rubber ) leaked terribly. Switched to cork.

There is still a leak though, nothing at all like it was, I dont know where its coming from, I know the crankshaft bearings were in pretty rough shape, I ended up removing them all to drop the crank to get the seal out. There was no chance it was coming out any other way in my opinion.

Anyway I was told by Fel-pro techline that if the bearing clearances were iffy on the rear bearing that no new seal was gonna fix the leak.

Im not sure that its leaking from the new seal, havent bothered to look that hard, again not dripping anything like it was, Im gonna buy a large drip pan to go under the truck, if it gets real bad again I have another 318 that sitting in a military truck that I believe has low miles and as far as I know will be in better condition.

I wont do another rear main like this in vehicle. I appreciate though the success and the opportunity I did have to do the job.
 
Well, some you win and others not so much, this sounds kinda like a "tweener" where you gained some but not quite enough to justify the effort.
 
You could try an oil additive called (Seal lube). They make several varieties. I have seen that stuff seal power steering boxes leaking a steady stream. Also, on the 318, isn't there a seal at the rear of the cam shaft or something above the crank, I don't remember. Might be seen from the dust cover?!?Also, maybe a small leak from the oil sender as I think that's back there on the top also but I might be wrong about that.
 
Yes Ive heard about the oil senders typically leaking but I didnt see anything when I had it on the lift but thats not saying much cause its nearly impossible to even catch a glimpse of the backside of the unit from down below never mind see an oil stain.

I may try the additive, at this point today its just not bad enough.
 
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