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Old 12-02-2008, 10:05 PM   #1
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Default what is invovled with replacing this bearing?

I've been working on swapping a 99 engine into my 97. The front seals of my transmission were leaking so I was going to replace them. I've been in a hurry, because I needed to be finished with this last week, but I've had set backs. I wasn't thinking and gouged out the cover on the bearing of the counter shaft thinking it was the seal I was replacing. Research FTW!

I am pretty sure the bell housing has to be removed so the bearing can be pressed out, and the new one can be pressed in. Anyone know if I just have to take of the bell housing or will it require more to get to the bearing.

If it is going to take more would it be worth rebuilding the transmission, and cryo treating the gears?

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Cool falcon I trapped in my shop a couple of nights ago...
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Old 12-02-2008, 10:34 PM   #2
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are you feeding the raptor at least? don't know about your bearing
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Old 12-02-2008, 10:50 PM   #3
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I would try and pop the bearing cover back, it should hold ok.

Why keep the poor bird trapped?
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Old 12-02-2008, 11:19 PM   #4
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I let the bird out of the shop after I got a picture. I hope I didn't scare him off, because he would be good pest control. I was pretty sure I was going to get my face ripped off after I took that picture.

I don't think the cover is going back on. Its pretty mutilated, and bent up. It has a few screwdriver holes in it.

My other option is a $100 FM salvage special which isn't looking bad right now.
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Old 12-03-2008, 03:17 AM   #5
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I'm not too familiar with cryo treating so that I can't answer. A rebuild might not be a bad idea if it's sloppy or has a lot of miles. They can be tedious if you do it yourself or expensive if you take it to a shop.

Usually the bell housing has to come off.There is actually a tool for this. You could probably fab some thing up but it's nothing a few strategic hits with a dead blow wouldn't get done.

IIRC the manual calls for a large gear puller to pull the bearing off and a special driver to get it on. You could probably use a piece of pipe to drive it on. Just make sure to drive it on with the edge of the inner race. Straight on the counter shaft, gently! Mine went on pretty easy.

Don't forget there's usually a shim between the cover and the face of the input shaft(main drive gear)bearing, that sets end play on the input shaft. The seal lips face backward and I think the book calls for thread sealer on the bolts. Got to reseal the case too.

If it's a koyo bearing I may have a seal laying around. I'll look tomorrow.If your really concerned about it and I find one , I'll just mail it to you.

Last edited by lordrigamus; 12-03-2008 at 03:38 AM.
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Old 12-03-2008, 08:54 AM   #6
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I would appreciate that if you find it. I would owe you big time.

What would the repercussions be of running without one? Or if I put the one I have back on, and it fell off in the housing once its all sealed. Should only be transmission fluid in the housing.
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Old 12-03-2008, 10:22 AM   #7
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Default ghetto case separator/puller

The main shaft bearing is pressed in the front section. You've got to separate the front from the mid and then press it out. Definitely replace it while you're in there and given it's condition. Here's how I cracked and separated the case (and some other pics).



there's your bearing... my countershaft bearing fell out.


the other side of the front section (inside)
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Old 12-03-2008, 07:08 PM   #8
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The case splitter is awesome!!! The gears don't look bad either. A little peening on the face of the gear teeth, not bad though. Mine were wore out in my '92 trans. I pulled apart a '91 and it was perfect. Weird

Are the syncros OK? Mine were beat up, I don't know why.

I've got a seal, It's from an NSK TM205. It's in good shape.
If you could use it PM me your address and I'll mail it to you. I"ll see if I have a KOYO. They may all be the same anyway.
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Old 12-03-2008, 07:43 PM   #9
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Don't worry about sending the cover. I'm going to try to make the one I have work. Its probably not a sealed bearing considering its in transmission fluid, and I remember transmission fluid being in the bearing. If it ends up failing after the fact I'll order a used transmission from FM. I have to get the car running again.
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Old 12-03-2008, 08:14 PM   #10
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My O E bearing was packed with grease and sealed on both sides. The bearing kit I bought had open ones without seals. I guess it doesn't matter as long as there is something in there to lube it.

All the ones I've ever seen have been open anyway. The first sealed one I ever saw was in my Miata trans.

If you run it open, make sure the open side faces the interior where the oil is at.Your seal may hold up anyway if it's not too bad. Good luck
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Old 12-04-2008, 12:04 AM   #11
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That's all it took to get that far. It's a lot more involved to get it all the way apart. A few special tools too.

Gear puller with different length legs, retaining and snap ring pliers, and an 18 inch deep well socket to mention a few.Nice piece of pipe to drive on the bearings and some time.

It took me a while to do mine but I was real ---- about it.
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Old 12-04-2008, 12:57 AM   #12
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I didn't bother taking that one apart since I had another sitting on the floor. Just need to move the front section over. But the one I pulled was making a loud grinding noise under initial load up and was hard to rotate by hand compared to the "new" one.
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Old 12-04-2008, 01:13 AM   #13
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Quote:
Originally Posted by jsisco View Post
Don't worry about sending the cover. I'm going to try to make the one I have work. Its probably not a sealed bearing considering its in transmission fluid, and I remember transmission fluid being in the bearing. If it ends up failing after the fact I'll order a used transmission from FM. I have to get the car running again.
Sorry to read about you damaging the cover......

Please post up and let us know the results once you are finished.

What are you using to control the VICS on the 99 head?
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Old 12-04-2008, 09:04 AM   #14
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Yeah I'll definitely post back if it makes it a few thousand miles or if it grenades.

I'm going to try to use the shift light output on my Megasquirt. I've heard that its possible, but I haven't heard a lot of talk of anyone having trouble. I have a feeling that no one talks about it, because its so easy to do. If for some reason that doesn't work I will just get a MSD rpm switch.
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Old 12-04-2008, 11:03 AM   #15
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Quote:
Originally Posted by jsisco View Post
Yeah I'll definitely post back if it makes it a few thousand miles or if it grenades.

I'm going to try to use the shift light output on my Megasquirt. I've heard that its possible, but I haven't heard a lot of talk of anyone having trouble. I have a feeling that no one talks about it, because its so easy to do. If for some reason that doesn't work I will just get a MSD rpm switch.
You have to build a circuit and other fucked up ****. I need to figure out what I'm going to do with it though because I need to get my **** on the dyno.
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Old 07-20-2013, 07:15 PM   #16
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Holy crap...i just did the same damn thing. I'm so pist at myself...Looks like 2 people have posted about making this mistake and both looked to have to just put it back together.

This was Dwayne hoovers logic for just putting it back together with the cover off.

Let me give you the logic we talked through in deciding to NOT DO ANYTHING:

1. Those bearings are NOT oil-tight. Oil works past the bearing seals and fills that transmission cover to the sump level. That's why it has a full perimeter gasket ... and why a few ounces of oil come pouring out whenever you take the cover off.

2. There are already open unsealed bearings inside the transmission. This bearing lives on gear oil, it doesn't live on grease that is sealed inside the bearing.

3. There is already a seal on the output tube of the front cover .. a REAL seal that actually seals.

4. So ... what is that seal REALLY sealing out? Nothing.

5. So ... by not having the seal, what are we exposing the bearing to? Well ... what did you find inside your cover? Nothing. Dirty oil that was no dirtier than what you drain out of the transmission.

6. OK, so why is the seal there then?

Possibilities:
-The bearing came that way/The bearing is used somewhere else where the seal actually matters
-To keep machining chips and other debris out of the bearing during manufacture
-They wanted the inside seal to protect against debris ... since it is low and forward it is far from the magnetic drain plug and could see more debris than normal due to braking?

Put it back together. You'll go through syncros, rod ends, and forks before that bearing ever fails.

There will be plenty of people telling you to spend $400-800 to fix your problem, but if that was your preferred option you wouldn't be here in the first place.
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