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.? |
Bartlett 914 |
May 5 2007, 07:19 PM
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#2
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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 |
The slider was worn. I am pretty sure that was the main problem the transmission had. It is why I got the parts to make the repairs. They were damn expensive. I was just a little supprised that it was not worn more than it was.
The fork questions were more of a follow up in looking for other things the transmission may need. I want to fix everything now and not later. I am pretty sure the first / reverse operating sleeve is O.K.. Haynes gives me a wear limit of .0197" for the fit in the sleeve groove. I am within that range. The others are almost new specs. I do not see specs for the other condition I measured. My concern is the amount of rocking the fork has in the sleeves. The .028" for the first / reverse may be fine but .060 for the others I suspect is too much. This is what I am hoping to find out. |
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