Transmission questions, Shifter fork tolerance |
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Transmission questions, Shifter fork tolerance |
Bartlett 914 |
May 5 2007, 05:43 PM
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#1
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Advanced Member Group: Members Posts: 2,216 Joined: 30-August 05 From: South Elgin IL Member No.: 4,707 Region Association: Upper MidWest |
I am rebuilding my transmission. The only real problem is the first / reverse operating sleeve. I had one on the shelf and a new syncro ring. The transmission had a problem jumping out of first. While I was there, I made some measurements. The shifter forks fit in the operating sleeves in a groove. There are 2 measurements I made. One is the wear on the thickness of the fork and how much slop there is in the groove. I used feeler gages to measure this. The other wear in more of a diameter of the shifter fork. As it wears the diameteter gets larger and the fork can rock in the sleeve. Here is a picture how I measured this.
The side clearence: Would rock (diameter wear) first / reverse .010" .028" Second / Third .003" .060" Fourth / Fifth .003" .060" It appears to me that the First / Reverse is worn thin. I think it is in specs. The other 2 seem to be worn in a diameter (fork would rock back and forth) maybe a bit too much. Can anyone tell me if these forks are O.K.? |
jimkelly |
May 5 2007, 06:33 PM
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#2
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Delaware USA Group: Members Posts: 4,969 Joined: 5-August 04 From: Delaware, USA Member No.: 2,460 Region Association: MidAtlantic Region |
I would suspect a bad 1st gear slider ( you refer to as operating sleeve - has worn teeth ) or bad dogteeth on first gear or likely both - are you saying all teeth in this area were ok ??
lets see some pics - not from top but from side of teeth - the fronts of the teeth on your 1st/reverse slider and your original 1st gear dogteeth. i can not imagine that a fork could be so bad as to cause gears to pop out provided it stays in the slider groove. i mean - the fork only moves the slider forward or backwards - once gear's dogteeth is engaged into the slider's teeth, the fork is not doing anything but waiting for a command from the driver. |
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