1G Newbie question: Replacing rear engine seal, will lots of oil leak out?

[XC92]

I've got my trans, pressure plate, clutch & flywheel off, and figured I might as well replace the rear engine oil seal while they're all out (got the Fel-Pro kit w/gasket) as good preventive maintenance even though nothing appears to be leaking. Never done it before but I understand it's pretty straightforward.

Thing is, being a seal, and with all the oil still inside the engine and pan since I didn't see a reason to drain it for trans/clutch work (I did drain the trans itself of course), will oil come gushing out or at least seeping through once I remove the seal case w/oil separator and seal, and do I have to work fast?

I'll have a drip pan under it just in case, but I'm wondering just how much to expect.

It's a 6-bolt, on a '92 Talon TSi AWD.

Btw, when I reinstall the trans, should I apply RTV (I have Ultra Gray) on either bell housing surface?

 

[AWD-Tony]

Can’t remember if I drained the oil and what level it’s at when it’s full. I’d say it’s close to there the pan and block mate. Lower the drivers side and keep the p/s raised and you should be fine. No rtv on bell housing. There’s no fluid passing between the block and transmission. Make sure you rtv between the oil pan and the bottom of the rear main seal cover. When you install it you can slightly push up so it does just push the rtv into the pan

 

[XC92]

Can't really lower the driver's side since the subframe's out with the engine supported by only 2 mounts and a jack/block under the pan, so I'll have to make do with the current level. I'm ok with some seeping, but a gush of old oil would be quite messy and I just want to be ready for it. I'll drain the oil if it's necessary, but if it's not I'd just as soon avoid that step if it can stay in.

 

[AWD-Tony]

Don’t forget the two bolts underneath on the oil pan that bolts to the rear main cover. Pry it slow to see how much comes out.

 

[2gmitsueclipse]

For 6-Bolt:
You will need to remove the housing for the rear main seal. I would recommend draining the oil to avoid contamination and/or oil leakage. Because of this, it may be a great opportunity to remove the oil pan and reseal it it along with the crank seal housing (Not required). Once the seal housing is removed, it is really easy to pull the crank seal. Here is a post that shows what to expect:
https://www.dsmtuners.com/threads/1990-eagle-talon-sleeper.427853/page-2#post-153027928

For 7-Bolt Only: The rear main seal can be replaced without having to remove the housing. If you are going to leave the rear main seal housing in place, it can be a challenge to get the seal out without scoring either the crank or sealing surface on the housing.
A method to remove the seal safely is to run a drywall screw through the center portion of the seal since it is reinforced. I wouldn't suggest a self-tapping screw as they can create small metal debris that can find their way into the sump. Here are some pics to demonstrate what I mean:

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The little notches on the OE seal you can see above are a great spot to drive ensure the screw is centered on the seal.

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The above pic is about as deep as the screw should penetrate the seal.

Once the screw grabs, only let it go through the seal enough to be able to use the screw as leverage for removal. There is a lip on the seal housing that you don't want to damage. With a seal as large as a crank seal, I would run a screw on opposite sides. Use some pliers to pull on the screw. Install the new seal with some oil/grease on the crank sealing surface to ensure the lip doesn't get caught/damaged when installed.

 

[AWD-Tony]

Mine came out with the cover so I removed it this way using a seal puller

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[pauleyman]

If you are going to leave the rear main seal housing in place, it can be a challenge to get the seal out without scoring either the crank or sealing surface on the housing.
A method to remove the seal safely is to run a drywall screw through the center portion of the seal since it is reinforced. Here are some pics to demonstrate what I mean:

You must be logged in to view this image or video.

The little notches on the OE seal you can see above are a great spot to drive ensure the screw is centered on the seal.

You must be logged in to view this image or video.

The above pic is about as deep as the screw should penetrate the seal.

Once the screw grabs, only let it go through the seal enough to be able to use the screw as leverage for removal. There is a lip on the seal housing that you don't want to damage. With a seal as large as a crank seal, I would run a screw on opposite sides. Use some pliers to pull on the screw. Install the new seal with some oil/grease on the crank sealing surface to ensure the lip doesn't get caught/damaged when installed.

Its been a long time since i did a 6 bolt but i want to say you can't pull the seal without pulling the housing. 7 bolt is different.

 

[2gmitsueclipse]

Its been a long time since i did a 6 bolt but i want to say you can't pull the seal without pulling the housing. 7 bolt is different.

Updated the above post to reflect both 6 and 7 bolt replacement.

 

[XC92]

Thanks all. It seems that every task I have leads to three others. And to think that this all started with a bad clutch that needed replacement. I'm probably going to have to cut short some of these tasks and do them later, as I've got to get the car out of where it is by the end of the week. So I'll do only the ones that have to be done, then when I have the car where it can stay a while, I'll do the rest, even if it means pulling the trans again.

Btw, I went to have my flywheel resurfaced today and there were two problems. One, the machinist doesn't have or use a dial mic (I think that's what it's called), as he generally doesn't work on flywheels, only rotors and engine parts. So he wouldn't be able to give me precise before and after step and height readings.

And two, the flywheel has some warping and glazing and is slightly thinner on its inside diameter vs. its outside, and he thinks that it doesn't have enough surface left to grind out all these issues and still be high enough to make good contact with the clutch disc. He thinks it may be past its useful life.

This would be its fourth clutch and I assume its third resurfacing, and the disc I'm replacing wore all the way down to metal, no friction surface left to speak of. Does this sound right, and is it time to get a new flywheel?

If so, since the car is stock and I don't race or launch or any of that, what do you recommend? I'm installing an SBC Stage 2 Daily Driver clutch kit. Steel or aluminum? The place said they could get me a Rhino Pac steel flywheel that weighs 16.25lbs, but I googled it and it looks kind of low-end.

Alternatively, if I'm just looking to drive the car to the driveway next door, and then maybe 5-10 or so miles back and forth to get it inspected, could I use the old flywheel, unresurfaced, until I've had time to figure out what to do, or would that ruin the new clutch?

Again, I need to get the car moving by week's end, and am looking to buy some time before finishing the rest of the work, and just want to make sure this won't be bad.

 

[XC92]

Thanks again. In order to get everything back together and move the car by week's end, I'm going to skip this for now and do it when I pull the trans again to fix an unrelated trans issue and also replace the flywheel. Since I didn't see any leak here and this is purely preventative maintenance, I can put it off for now.

When I do get to it, I'll drop the oil pan since I'm replacing the oil anyway and it's been years since the pan has been cleaned (if it ever has been since I've never done it), so I might as well do all of these at the same time.

I'm also going to replace the timing belt and everything else there pretty soon, so that might be a good time to do that too, since I might want to replace the oil pump seal and others parts there too.

"Phase One" is nearly over, getting the car in safe and driveable shape again so it can be inspected, registered and insured, and able to be moved as needed. "Phase Two" will be to take care of all these maintenance tasks that need to be done, e.g. changing all fluids, filters, belts, seals, etc., new pads/rotors, struts, hoses, etc.

 

[XC92]

The trans is dropped on my '92 Talon TSi AWD so I figured I might as well replace the rear engine seal while it's out. It doesn't appear to be leaking but it seems like good preventive maintenance.

However there does appear to be a leak somewhere, most likely of engine oil. I'd thoroughly cleaned the underside of the engine and basically everything under the car in the engine bay area that I could access earlier this year, as it was pretty dirty and oily, and replaced the oil and filter.

But now around half a year and several hundred miles later, there's quite a bit of oil around the oil pan area, so clearly there's a leak, just not from the rear seal area. As best as I can tell the RTV between the pan and engine is breaking down and the source of the leak, so I need to drop the pan, clean it and reinstall with fresh RTV.

My main question is, is there any particular order I need to do this if I'm dropping the pan AND replacing the rear seal, in terms of removing and then reinstalling each? Do I need to remove the pan in order to remove the seal? And then do I need to install the new seal and then the pan? Or vice-versa? Any other tips, tricks, watch out for's, etc.?

Also, once this is done and the trans is back on, I plan on doing a complete timing belt replacement. I.e. timing and balance belt, idlers, tensioners, water pump, etc. Should I also replace all the seals on that (i.e. front) side then? Or is this better done when I have the pan dropped?

Btw I bought a Fel-Pro rear seal. Is that a bad idea and should I get an OEM?

And I'm planning to use Ultra Black RTV. That's the right kind, right?

 

[Mech Addict]

So when you intend to replace the t-belt, were you planning to remove the oil pump/ front cover anyway? That can be a source of oil leak, but if it isn’t, and you have no issues with the pump, then normally you’d leave it on. The t-belts and tensioners and all the pulleys are bolted to the outside of the front case (or block). The pan bolts into the front case in a few places, so it’s easy to remove the pan without taking off the front case, but not so easy the other way around. I think FSM shows the pan removal as one step in the front case removal.

 

[XC92]

So when would I remove the front case if I'm not rebuilding the engine or need to get at the internals, e.g. camshaft, crankshaft, etc.? I assume that it doesn't need to be removed for even a complete TB job or oil pan drop? If the oil pump is leaking, does the front case need to be removed? Obviously if I do need to remove the front case for some reason, I'll do it when I drop the pan since I was going to do that anyway.

Sometimes it feels like I'll never finish this "restoration", that there will always be yet another task that needs to be done for the car to be "right".

 

[Mech Addict]

If you suspect the oil pump was going, like low pressure. Or to do something to the balance shafts, like new bearings or delete. Or if the gasket was leaking. Those are the obvious ones to me. Of course removing the front case wouldn’t always be the first, best step if you had low oil pressure, since many things can cause that. But as troubling shooting points to the pump, you would pull it and inspect.

 

[XC92]

I guess I first need to clean everything, replace the rear seal and drop, clean and reinstall the pan with fresh RTV, and see if that fixes the leak. If not, I assume that I'll be able to tell where the leak's coming from after running the engine a few minutes, perhaps with the front still up and just the flywheel installed. If I wait too long the mess will spread out enough that it might be harder to pinpoint it. When I do the TB job though, is it good practice to replace all the seals on the front case?

 

[Mech Addict]

Finding oil leaks can be tricky sometimes, because a small stream of oil can run down from one place and leave a big mess elsewhere ( like on the pan, since it’s at the bottom). But certainly that has a large sealing surface that could develop a leak.
as far as order on the rear seal or pan, I think 6-bolt requires the pan be removed first, but 7-bolt it can be done either way. Does your seal retainer have pan bolts going up into it? That would pretty much determine it. Plus if the pan is off, you get a better view of the seal on the “inside”, no?

You’re going to run the motor with the trans and flywheel off?

Also occurs to me now that the front crank seal is housed in the front case, and that could be leaking. You’d notice during the TB job.

 

[NOSLO2PT0]

Installation of the oil pan should be dead last. If you need to pull the front case/oil pump, the oil pan must be off. And you want to use Ultra Gray rtv

You’re going to run the motor with the trans and flywheel off?

That’s impossible to do on a 4g63

 

[XC92]

You’re going to run the motor with the trans and flywheel off?

As I wrote above:

after running the engine a few minutes, perhaps with the front still up and just the flywheel installed

Bit perhaps this might still be a bad idea since the engine really has 4 mounts, three directly connected and one via the trans, which the engine is firmly bolted to. It might vibrate and the harmonics could destroy things. So I won't.

But as I like to say, there's no harm whatsoever in trying questionable if not outright crazy ideas, so long as it's just in your head or a simulation.

And even then I sometimes get nervous!

That’s impossible to do on a 4g63

Not that I would ever consider doing this (and have ruled out doing it even with the flywheel, clutch disc & PP installed, for reasons given above). But, why is it not possible, as opposed to just a very stupid thing to do? What prevents it, some lockout mechanism or the like?

Installation of the oil pan should be dead last. If you need to pull the front case/oil pump, the oil pan must be off. And you want to use Ultra Gray rtv

Thanks. I have both Ultra Black & Gray, so I'm good.

 

[NOSLO2PT0]

The starter is mounted to the trans case. How were you going to start the car without the trans mounted?

 

[XC92]

Well I suppose that in theory I could do it the way they used to 100 years ago, with a crank on the crankshaft pulley bolt. But, yeah, point taken, I don't know why I didn't remember that.

 

[XC92]

Btw am I losing my mind or have the mods been merging threads and comments today, pretty aggressively, and if they have, have I been violating site rules by starting new threads that relate to old threads I started a while back and haven't touched in a while, and is that BAD? And is raising questions about site rules & policies in public forums itself not allowed? Some sites I've been on take this stuff REALLY seriously.

 

[steve]

You're not breaking any rules but the history is usually important if for no other reason that to cut down the duplicated guessing. It also makes it much easier for someone down the road to track what was done to fix a problem they might be having.

It is frowned on to post back to back messages rather than editing a prior one. That's part of why there is the multi-quote feature. Click on the "+quote" and then when you repla you can copy all of them in and reply.