rear main seal

[riverfever]

I know that Fel Pro makes a double lip rear main seal. I'm trying to figure out if it is different than the seal from NAPA. I ask b/c the NAPA seal has the main lip as well as a small dust seal. Anyone know?

[5-90]

"Double Lip" refers to two actual sealing lips - not a wiper lip and a dust lip. So, the "double lip" from Fel-Pro should be different from the NAPA seal you're looking at.

The purpose of the "double lip" seal is similar to an "offset lip" seal - it relocates the effective sealing element, in the event that there is a "wear groove" where the seal normally rides.

Make sense?

5-90

[riverfever]

Yes that makes sense 5-90. I did this repair over the summer but it's leaking bad again so I'm going to drop the pan again and see what it looks like. Is there anything special I should do when installing the bottom seal? I just popped it in that groove in the cap. I did apply RTV to the sides but I'm not sure why I'm leaking again. Seals were installed with the v towards the internals of the motor.

I did find a Fel Pro seal. Maybe that will help. I do not recall any groove in the crankshaft but I'll look closer this time.

[riverfever]

For anyone that searches for double lipped rear main seal in the future:

The part # that I found in the archives for the Fel Pro double lipped seal was BS40612. It is the exact same seal that I got from NAPA and it's a single lip. I did find a double lipped seal from Fel Pro but it was special order only and it was 32.99 instead of 14.99. I ordered one but it wont be here for a few days. I will post pics of the single vs. double seal.

5-90...maybe these part #'s would be a good idea to include in your write up in the FAQ. This time around I am going to try and takie detailed pics of the repair. If they turn out good then maybe those might help the visual learners like me?

[5-90]

I'm already on it. I finished getting the relevant information out of the Fel-Pro catalogue a while ago - I just haven't had a chance to code it into .html yet.

And, I'm doing a lot more than the Fel-Pro catalogue!

I'll post updates here as I get them done, and if NAXJA wants to host them as part of their/our FAQ project, just let me know how to format it...

5-90

[riverfever]

I'm a little miffed now. I thoroughly cleaned everything off and then started the motor up. It idled for 15 minutes and I saw no traces of oil. The the wife came out and she brought the RPM's to 2k and blipped the throttle to 3k off and on for about another 30 minutes. Finally I saw traces of oil. The back of the head and the filter adapter are completely dry. I snapped some pics under there:

This one shows a little bit of oil coming from the tiny slot on the bottom of the starter but more coming from the bolt that holds the bottom part of the starter on.
http://i9.tinypic.com/3ydmat5.jpg

Another shot of that lower bolt on the left side of the pic:
http://i10.tinypic.com/44970vr.jpg

Another:
http://i9.tinypic.com/4i6lwsn.jpg

Here's a shot of the inspection plate. You can barely see the end of the crankshaft from this view and it's dry as a bone:
http://i7.tinypic.com/2lu2tk6.jpg

Another shot of the back pf the pan:
http://i10.tinypic.com/29m2jc4.jpg

I'm wondering if this leak is coming from the upper portion of the rear main seal? Maybe it's phukt and slinging oil inside the bellhousing under real heavy loads? I've got the double lip seal coming and I'll put it in for added insurance I guess. I don't see how the oil could come from anywhere else.

[sflier]

A leak like that is probably coming from the o-ring that seals the oil filter housing to the block ... the most common leak in these engines. It's cheap and easy to change and very very often miss-diagnosed as a rear main seal leak. Search on this forum and you'll find a couple of decent write-ups with some tips.

[riverfever]

sflier...o rings are new as well as the valve cover gasket. I'm fairly confident that I phukt up when installing the upper part of the rear main.

motofreak...I read/speak English so that really doesn't help. Not sure if it's SPAM or what.

[sflier]

Ooops, my bad ... I do see now that you wrote that the filter adapter is completely dry.

[SteveT]

Yes that makes sense 5-90. I did this repair over the summer but it's leaking bad again so I'm going to drop the pan again and see what it looks like. Is there anything special I should do when installing the bottom seal? I just popped it in that groove in the cap. I did apply RTV to the sides but I'm not sure why I'm leaking again. Seals were installed with the v towards the internals of the motor.

I did find a Fel Pro seal. Maybe that will help. I do not recall any groove in the crankshaft but I'll look closer this time.

I'm not sure what you mean when you say "...with the v towards the internals..." The open end of the v should be toward the internals, not the pointed end. Not sure if that's what you did, just looking to clarify.

Steve

[lawsoncl]

That doesn't look like a rear main leak to me. I'm more inclined to think the pan seal is messed up. I assume the back of the block is dry, which would point to the valve cover? Crankcase vent is clear?

[riverfever]

Steve...yes it was vague. I meant to say that the open end of the v was facing the internals.

lawson...I don't know. I just picked up a new double lipped rear main seal. I'm going back in on Friday.

[5-90]

Two more things -

1) Use the newer (96-up, I think) gasket. It's one-piece moulded rubber, and seals better. It worked on my 88...

2) Check the oil pan rails when you get it off. Lay the edge of a ruler on them and make sure they're flat! Use a light (less than 2#) hammer, a brass or bronze rod (steel OK, but may dimple the pan - making for more work!) and a large flat piece of wood to tap the pan rails back into shape, if necessary. I've had to fix so many leaks caused by some hamhanded SOB prying off the pan and not checking that it's just automatic for me anymore. Since I don't consciously think about it anymore, that's why it took me so long to mention it...

5-90

[riverfever]

That is the gasket that Lawn Cher and I installed in St. Louis over the summer.

Good call on taking a ruler to the edges of the pan though 5-90. That could very well be an issue.

[riverfever]

As soon as I dropped the pan I noticed a small tear on the passengers rear of the pan gasket. Not all the way through but enough. That's the second time that's torn in that location. I figured I'd check the rear main while I was that far. Small cut on the top of the upper seal (very small). I installed the Fel Pro double lipped seal. The first time I did the pan gasket over the summer, I was on my own and I know the tear was a result of my forcing it blind. The second time that I did it, I actually had good help but it still got cut. Not sure why. The oil pan gasket on this motor is definitely one of the more finicky gaskets I've done. Oil pan looked fine. It was straight with no dimples where the bolt holes are. I used another one piece gasket with black RTV on both sides. Everything went back together OK. I did have one of the smaller bolts strip out on me (I believe it was the block that stripped). It's on the drivers front corner and it's the bolt that has the larger one right next to it. It does not appear to be leaking right now after 2 days so I'm hoping that the larger bolt is taking care of things.

[Powerman]

Hey River, I plan on doing this this Winter. My main is leaking as well as the filter housing. How long did it take to repace the rear? How long of a job should I expect it to be? I wouldn't expect the filter housing to take more than 30 minutes with the rest of it apart.

[riverfever]

Hey River, I plan on doing this this Winter. My main is leaking as well as the filter housing. How long did it take to repace the rear? How long of a job should I expect it to be? I wouldn't expect the filter housing to take more than 30 minutes with the rest of it apart.

Kevin,

You're probably a little better at this type of stuff than me. I obviously have trouble knowing if a seal is positioned correctly, as well as getting the pan gasket in place properly. This time around I had air tools and a lift which made the job really enjoyable. After I got everything removed, I took a lunch break for close to an hour. All said and done (with help installing the seal and gasket) I was probably right at 4 hours. I had to unbolt the steering and track bar when I went to put everything back together b/c the lift didn't allow the axles to droop quite enough. Hope that helps.

I agree...with the starter removed, you should have more room to get that filter adapter off easier and do those o rings. Half hour sounds totally reasonable for that.

[caz]

Bringing this one back from the dead.... Did the stripped bolt(s) ever cause you any more problems? My current leak is happening exactly like yours is and if it drips, it drips from the bottom like that. It's wierd though... sometimes it will leave a drop over night and then it won't leak at all for a week. However, I have two bolts that are stripped, one on the front and one that the head of the nut broke off on one of the sides (can't remember which side). Did they ever cause you any other problems? I'm going to redo both my pan and rms w/ black rtv over the next couple of days... Thanks :)