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6 speed woes

 
Old 03-24-2019, 09:13 PM
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Default 6 speed woes

preface: i have never done transmission work before, but i did my homework before cracking into it
story: picked up a cheap 6 speed. 5th and reverse would not engage. Was planning on opening it up, so diagnostically removed the donotremove pivot bolt, (bolt took a few horsetorques to remove) Clunk. Can confirm was not the issue.
Yank the bell housing off and fight with bolt for a while. After one beer, i clean off the threads and make sure the bolt goes through them butter smooth and that the bolt goes through the lever. After beer #2, i got it lined up but the bolt wasnt happy about going into its home. Pull it out and now the bolt wont go into the hole, even after some mild machining with a file. Ive given up for the night but crave input.

1) does anybody have spare of these items from a grenaded 6 speed?
2) what would have caused 5th/r to not engage before donotremove was removed initially? I heard it fall when i pulled it for sure.
3) am i barking up the wrong tree; could my problem be elsewhere in the trans?

Last edited by WigglingWaffles; 03-24-2019 at 10:43 PM.
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Old 03-25-2019, 10:38 AM
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1. I have parts from 2-3 different transmissions I took apart last year. Shoot me a PM with the pictures of what you need and I'll pull them.
2. I had a similar issue. I had a trans that wouldn't engage reverse. I found that there are bushings in the shift forks that can work themselves out. In my case it had work its way out and wouldn't allow the shift fork to move enough to engage the gears. I'll have to check if I have one of these to spare. We had to check a few to make sure they were in good shape when I did my rebuild.
3. Look very closely at your 5-R shift fork, I bet that's the issue.
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Old 03-25-2019, 07:46 PM
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I just finished rebuilding my AZ6 over the weekend. I hope you downloaded the service manual.

Can you engage all other gears except 5th and reverse? You should be able to row the shifter and spin the input shaft by hand. That would immediately narrow it down to the clutch hub or shift fork if all other gears work.
The 5th / Rev clutch hub is unique because 5th gear is on the input shaft and the clutch hub and reverse gear are on the main shaft. I could see a situation where the clearance opens up between the input and main shaft and you overstroke the clutch slider trying to engage 5th, which would cause the synchro keys/ball bearings/springs to fall out or even just bend the springs and jam the slider on the clutch hub.
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Old 03-25-2019, 08:52 PM
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Prior to surgery, all other gears functioned properly except 5/R. It felt like hitting a wall and refused to engage.

To my untrained eye, nothing in the gearbox looked amiss or out of place. I filed the bolt and pivot until the bolt went in and out smoothly, then greased it up before replacing the bell housing and now it goes into every gear properly.
My theory is simply that the bolt and pivot seized together. Ill report back (hopefully this weekend) when I have the shifter rebuilt and the trans in the car.
As it sits on the bench, it goes into every gear and feels like it should though.
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Old 04-06-2019, 07:46 PM
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Update + closure

Trans went into all gears on the bench. Installed it today. All gears function normally. Shifter still needs rebuilt though. I notice that Moss has two different kits for 6 speeds, how do i know which one is right for my trans? Theres no visible VIN on it if that matters.
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Old 04-06-2019, 09:22 PM
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Originally Posted by WigglingWaffles View Post
Update + closure

Trans went into all gears on the bench. Installed it today. All gears function normally. Shifter still needs rebuilt though. I notice that Moss has two different kits for 6 speeds, how do i know which one is right for my trans? Theres no visible VIN on it if that matters.
Mid year change in 2001. The size of the ball at the end of the shifter determines it
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