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(Not*) Mediocre 242

I pulled my trans and took it apart to check out the fifth gear assembly. Here is how I had it assembled:

Slider with the big chamfer out
UGLkt22l.jpg


Thing that holds the keys with the step out to fit the lock ring
qIfyx4tl.jpg


Fifth gear as normal
6aZ1pF4l.jpg


Upgraded bearing retainer
dYTTjyQl.jpg


Is something wrong with this setup? I think it's the only way that makes sense. My keys didn't seem really out of place either. Do the brass syncros have to go on a specific way? What else could be causing my fifth gear to pop out? My fluid does look metallic in the catch pan.

I also learned I'm using the wrong hydraulic throwout bearing for my pressure plate. It has flat fingers, so I should be using a radial bearing like Culberro. That's an expensive lesson.
 
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Is there a brass synchro between the slider and 5th gear?

The 3 that I have had apart have all looked like this:
 

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For the release bearing, you can get just the bearing and not have to replace the entire unit. Still ~$50 though: http://tiltonracing.com/product/replacement-52mm-radius-face-bearing-kits/

On the trans, does the slider snap into the keys? Were the detents in the slider matched up with the keys? The slider should be somewhat difficult to move by hand.
What's the end-play on the mainshaft and countershaft? Maybe it's rocking a bit under load and popping out?
 
For the release bearing, you can get just the bearing and not have to replace the entire unit. Still ~$50 though: http://tiltonracing.com/product/replacement-52mm-radius-face-bearing-kits/

On the trans, does the slider snap into the keys? Were the detents in the slider matched up with the keys? The slider should be somewhat difficult to move by hand.
What's the end-play on the mainshaft and countershaft? Maybe it's rocking a bit under load and popping out?

I already have one of the 52 mm radius face bearings. Unfortunately, it doesn't work with my piston, so I ordered a new one of those too. I'm just glad I don't have to buy a new hydraulic base. That's the expensive bit.

The inner part of the slider assembly slides around in the outer part while the keys remain in the neutral position. There is no end play in either shaft. That's the whole reason I took the transmission apart. Second gear would pop out on downshifts. After I adjusted the play on both shafts, it stays in second no matter how hard of a downshift. So I don't think that's the problem either.

I ordered new 5th gear syncros, keys and springs. I'm hoping I just did something wrong with installing the keys last time because I have no idea what else the problem could be. In any case, parts should hopefully be here by next weekend and then I'll install it again and hope I didn't mess up.
 
I replaced the 5th gear syncros, keys, and springs with no problem. But when shifting to reverse, the reverse slider moves the 1-2 slider, which seems wrong to me. Does the 1-2 shift fork hold that slider in place during normal operation?

<iframe width="560" height="315" src="https://www.youtube.com/embed/41H7l3BlZJ0" frameborder="0" allowfullscreen></iframe>
 
Since I had the transmission out, I decided to address the heavy clutch pedal feel. The problem was that the flat face bearing I was using reduced the moment arm on the flat pressure plate fingers.You can see where it was hitting here:

GkB9exml.jpg


The solution is to get a radius face bearing. These are made to work with flat finger pressure plates, but I didn't know there was a difference when I ordered my bearing originally. You can see the difference between the flat face (left) and radius face (right) bearings:

BbeUtohl.jpg


f0b6TlLl.jpg


Unfortunately, the radius face bearing requires a different piston because it has a smaller inner diameter than the flat face bearing, so I had to change that as well. To install the bearing, I put the piston in the freezer for a couple hours and the bearing slid on no problem. Tilton said you could use a small press. It really doesn't require much. There should be a small gap between the bearing and piston step, so don't try to push it down too hard.

For reference the Tilton part numbers are:
Piston 62-612
Bearing 62-002

I got my piston from Summit and my bearing from Pegasus racing because they had them in stock.

To meet the smaller ID of the radius face bearing, the piston has a step. The flat face housing has an inner threaded section that is 0.140" taller than the housing that comes with the radius face bearing, and hits the step of the new piston. This reduces the overall travel of the bearing, but the Tilton engineer I talked to said he didn't think it would be a problem. I'll see when I actually install the transmission in the car. The pressure plate doesn't need to be actuated that much, and I'll still have 0.435" of travel accounting for the air gap when the bearing is fully retracted.

To get the new piston to fit, I had to modify the input shaft bearing retainer pretty heavily. I cut the nose down so that it was shorter than the threaded section, but I also had to remove some aluminum from where the threaded adjustment sleeve rests to get enough distance to properly adjust the new, longer bearing. You can see the machining marks here. I scratched the sleeve a bit, but it shouldn't be a problem because the adjustment sleeve still sits securely. It was a pretty easy job, just 30 min or so on the lathe. A professional machinist could surely do it faster.

gzfwvqll.jpg


You can see that the threaded adjustment sleeve is longer than the bearing retainer sleeve:

W239U2wl.jpg


Lif5Z8El.jpg


I adjusted the bearing to rest 0.125" above the pressure plate fingers and installed the bellhousing.

Hl0jS5Vl.jpg


DnukAopl.jpg


I'm a little concerned that the bleed hose isn't much higher than the pressure hose, but I hope to be able to get all the air out with my power bleeder. I'll try to install the transmission in the car tomorrow. Hopefully the release bearing is fine and fifth gear works. If it doesn't I have no idea what's wrong with my transmission.
 
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My son sent me this thread, impressive build!
Looks familiar in many ways.......

My experience with transmissions popping out of gear has always been related to the shafts "walking" in the case. Admittedly, most of this is Saab experience where the main shaft is also the pinion gear, but I have seen it on the Muncie trans that come in the "old" muscle cars.

Another comment, there is a picture of the input shaft housing (if that's what its called) with a couple of bolts in it. I didn't see any marks on the bolts indicating the grade of the bolt. No marks, usually means cheap bolts ( grade 2, or worse, from China), which you don't want to use. I'd go grade 5 (three radial marks). Some people always go grade 8 (5 marks), but that's not always the best way to go, and would be overkill.
 
I replaced the 5th gear syncros, keys, and springs with no problem. But when shifting to reverse, the reverse slider moves the 1-2 slider, which seems wrong to me. Does the 1-2 shift fork hold that slider in place during normal operation?

That's from the reverse idler sliding into the side of the 1-2 slider. The 1-2 shift fork keeps it from moving when it's actually going into reverse. If you keep the 1-2 slider in the "neutral" location, it'll go into reverse. If you let the slider move rearward and engage 1st, you couldn't rotate the trans by hand.
 
My son sent me this thread, impressive build!
Looks familiar in many ways.......

Thanks! Sometimes I feel like I copied his car, but his car is definitely much cleaner and nicer than mine. His car is definitely a huge inspiration to me.

My experience with transmissions popping out of gear has always been related to the shafts "walking" in the case. Admittedly, most of this is Saab experience where the main shaft is also the pinion gear, but I have seen it on the Muncie trans that come in the "old" muscle cars.

The reason I even went into the trans was to reshim the counter gear so it would stop popping out of second, so I don't think the 5th gear issue is shaft movement. But that was a problem I had.

Another comment, there is a picture of the input shaft housing (if that's what its called) with a couple of bolts in it. I didn't see any marks on the bolts indicating the grade of the bolt. No marks, usually means cheap bolts ( grade 2, or worse, from China), which you don't want to use. I'd go grade 5 (three radial marks). Some people always go grade 8 (5 marks), but that's not always the best way to go, and would be overkill.

Thanks for looking out for things like that. Fortunately, those bolts are class 10.9. They're probably overkill anyway because the torque spec is something like 16 ft/lbs.

That's from the reverse idler sliding into the side of the 1-2 slider. The 1-2 shift fork keeps it from moving when it's actually going into reverse. If you keep the 1-2 slider in the "neutral" location, it'll go into reverse. If you let the slider move rearward and engage 1st, you couldn't rotate the trans by hand.

That's what I was hoping when I reassembled. Thanks for the confirmation.
 
Let's see a big version of that Sig pic.

Is that shift fork boot a new one? Where did you get it? I run mine sans boot, But seems like I probably should have one.

Keep up the good work.
 
Let's see a big version of that Sig pic.

Is that shift fork boot a new one? Where did you get it? I run mine sans boot, But seems like I probably should have one.

Keep up the good work.

What sig pic?

I got the boot new from IPD or FCP a couple years ago.

I installed the transmission tonight and took it for a test drive. The clutch feels so much better. It feels like a stock cable clutch. Huge improvement, totally worth the time and money.

However, my transmission still pops out of gear. Now it's fifth and second. This makes me think it's something to do with the shifter, so I'll drive it to work tomorrow with no tunnel foam and no shift boot to see what happens. I'll also adjust my stops out again.
 
I installed the transmission tonight and took it for a test drive. The clutch feels so much better. It feels like a stock cable clutch. Huge improvement, totally worth the time and money.

yeah! Happy to hear this, and also glad you broke the path on this one. Really excited for a lighter pedal now :)
 
What sig pic?

I got the boot new from IPD or FCP a couple years ago.

I installed the transmission tonight and took it for a test drive. The clutch feels so much better. It feels like a stock cable clutch. Huge improvement, totally worth the time and money.

However, my transmission still pops out of gear. Now it's fifth and second. This makes me think it's something to do with the shifter, so I'll drive it to work tomorrow with no tunnel foam and no shift boot to see what happens. I'll also adjust my stops out again.

My bad, Avatar pic
 
Thanks. It's from some Saab. I don't know which one though, My friend had it sitting in his garage for a long time. If you're curious, I could grab the part number if you want.
 
yeah! Happy to hear this, and also glad you broke the path on this one. Really excited for a lighter pedal now :)

i really, really enjoy when harald and tate trial & error their way through something so i can just copycat it later.
 
Thanks. It's from some Saab. I don't know which one though, My friend had it sitting in his garage for a long time. If you're curious, I could grab the part number if you want.

1st gen 9000 spoiler I think? although I thought they had more wrap on the corners.
 
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