Bearing on primary drive cover , c900/99

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Mezzanine
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Bearing on primary drive cover , c900/99

Postby Mezzanine » Sun Mar 09, 2014 4:33 pm

Even a n/a 8V SAAB can kill its transmission if you wait long enough!

Three weeks ago the trans in my '85 900s notchback started to get really loud in reverse. Growly, sort of sounded like gravel in the transmission. Two weeks ago, first gear started to make a very loud clicking. Alarmingly loud. So, I did what any good procrastinator would do and I just started the car in second gear all the time. I thought I'd ride that out as long as possible, but in short order things started getting worse. I could hear a little bit of the clicking in other gears too, and it popped out of gear in 2nd a few times.

I have a nice 5-speed in a chill-cast case with a Quaife differential sitting on the shop floor ready to go, so I decided to make the swap this weekend. Pulling the engine was a lousy task since it has never been out of the engine bay in it's 375,000 miles. Super grimy and I'm very nervous about getting it to ever run again since I disturbed the very crumbly wiring insulation to get the engine out.

I finally got the engine on the hoist late last night, so I started the day off prepping the new box to go on. Since my car has the earlier style horizontal barrel motor mount, I had to swap the primary drive cover from my dead box onto the new one. Here is where I ran into some trouble. The new box has a bearing that supports the lower sprocket of the primary drive by fitting into the front cover. Here is a photo of the bearing:
trans_bearing.jpeg
primary drive front bearing
trans_bearing.jpeg (140.13 KiB) Viewed 2328 times


Here is the cover that I need to use. You can see that the casting has a place for the bearing, but it is .050" too small since it never had the final operation to mill it out for the bearing. I have TWO of these front covers, and neither is machined for the bearing.

trans_cover.jpeg
front cover without finish machining to support bearing
trans_cover.jpeg (160.04 KiB) Viewed 2328 times


The trans I want to put in is definitely a mutt- it is a 4 speed chill-cast case, with 5 speed guts. Scanwest just went over it when I had them install the Quaife, and gave it a clean bill of health. It was rebuilt by a fellow enthusiast within the last 6,000 miles.

My question: I can't find anything about this bearing in any of my manuals, but is there a year/engine combo that has the front cover I seek? Or can I just remove the bearing? Any suggestions on how it comes off? It looks like it is just press-fit to the shaft.

I can always modify the motor mount on the car to fit the other style, but if I don't have any choice, then that's what I'll do.
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nutcase
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Re: Bearing on primary drive cover , c900/99

Postby nutcase » Sun Mar 09, 2014 4:40 pm

I believe you can just leave the bearing off assuming there's the depth in the front plate.

The bearing was only used on turbos for a year or two.

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Mezzanine
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Re: Bearing on primary drive cover , c900/99

Postby Mezzanine » Sun Mar 09, 2014 4:47 pm

Here is a video I made to document the sound the transmission was making if anyone is curious:

http://youtu.be/T_KRTfYTVt8

I recorded it with my phone, so the quality is just what you'd expect.
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squaab99t
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Re: Bearing on primary drive cover , c900/99

Postby squaab99t » Sun Mar 09, 2014 11:06 pm

nutcase wrote:I believe you can just leave the bearing off assuming there's the depth in the front plate.

The bearing was only used on turbos for a year or two.

I think Nutcase is on the right track.
With the 5 speed I see dual tapered roller bearings. I can't see that bearing cartridge on the end having much affect on flex reduction. Nice belt and suspenders feature, but for your application no need.
5 speed.jpg


Now the 4 speed I can see were it might help the single bearing cartridge.
photo 1 (2).jpg


The last pix has no end bearing, for what that is worth.
primary.jpg


This is what you have been waiting for to add that quaife to the equation.
The last few seconds on the vid made me cringe.
Dennis

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DrewP
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Re: Bearing on primary drive cover , c900/99

Postby DrewP » Mon Mar 10, 2014 12:29 am

Craig, what are those big green things sticking out of the ground next to your roads?*

Are you gonna tear into it to see what failed? Tho at 375,000 miles the point so probably moot anyway.
"You can educate ignorance, but you can't fix stupid."

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Mezzanine
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Re: Bearing on primary drive cover , c900/99

Postby Mezzanine » Mon Mar 10, 2014 10:25 am

Drew, those green things are the weeds that grow around here called Doug Fir trees. We have a lot of them.

I do plan on tearing the box apart to check it out. I pulled the side covers off and it is pretty clean inside, but the transmission fluid was starting to turn into grease. Lots of dark metal particulate in there. Note that this transmission has had a very noisy pinion whine for years now. Years.

I'm now in the conflicted state of trying to determine how much work to do cleaning and replacing things while I'm in here. I have been slowly working away at building up my new 16v motor, so this whole premature trans swap has me a little put out. I wanted to do it all at one time, but instead I get a little extra practice. Lucky me. I don't think I'll be replacing anything on the engine, even though main seals couldn't hurt.

I'd taken the AC out of the car many years ago, which left me nothing to pick the engine with on the firewall end, so I had to make up this little bracket:
engine_bracket.JPG


A lot of work for a little bracket that I'll only use twice, but it got the engine nicely balanced when I picked it out.

Do you guys re-use the metal trans-to-block gasket, or just take it out and use some 518 or gasket maker? The one on the engine was only slightly mangled upon disassembly.
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Crazyswede
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Re: Bearing on primary drive cover , c900/99

Postby Crazyswede » Mon Mar 10, 2014 11:55 am

Mezzanine wrote:
Do you guys re-use the metal trans-to-block gasket, or just take it out and use some 518 or gasket maker? The one on the engine was only slightly mangled upon disassembly.



you can get a new engine/trans gasket...they are not expensive and I would not use sealant in its place....though you do use some sealant with the metal gasket.
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Geoff
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Re: Bearing on primary drive cover , c900/99

Postby Geoff » Mon Mar 10, 2014 12:32 pm

The kind of dirty that doesn't wash off :eyebrows:


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