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| | | | Joined: Feb 2001 Posts: 1,096 'Bolter | | 'Bolter Joined: Feb 2001 Posts: 1,096 | I have been asked to fix a gearbox, It was hard to get into second and would jump out of that gear.
I've pulled it apart , and another 3 g/boxes and everything is worn.
I find it hard to tell what actually causes this defect as I have no new parts to measure.
For example , what end float should there be on the main shaft?
How thick for the 2nd gear thrust washer?
Who might have new syncro hub / gears etc?
What else might cause it to come out of gear?
Thanks for your thoughts.
Last edited by Dusty; 02/25/2015 8:25 PM.
| | | | | Joined: Feb 2001 Posts: 1,096 'Bolter | | 'Bolter Joined: Feb 2001 Posts: 1,096 | Still struggling with a solution for this issue .
Surely someone has found a fix for this (now common) wear item. | | | | | Joined: May 2001 Posts: 1,907 'Bolter | | 'Bolter Joined: May 2001 Posts: 1,907 | All I can say is I had a '39 Master Deluxe car 50 years ago. Yes, half a century!
It had some kind of vacuum assist for shifting up-gear but the dang thing would help it shift out of gear to neutral when I backed off in high.
Not much help here.
1948 3/4-Ton 5-Window Flatbed Chevrolet 34 Years. Now with a '61 261, 848 head, Rochester Monojet carb, SM420 4-speed, 4.10 rear, dual reservoir MC, Bendix up front, 235/85R16 tires, 12-volt w/alternator, electric wipers and a modern radio in the glove box.
| | | | | Joined: Aug 2010 Posts: 775 'Bolter | | 'Bolter Joined: Aug 2010 Posts: 775 | When I found a place in Portland OR who had an older guy who knew all about the three speeds. He indicated that when the syncros are worn they will pop out of gear. He indicated the only fix is to replace the syncros. They don't make these anymore. He rebuilt mine because the difference between the parts and him doing the work was 100.00. He said he had hundreds of the transmissions. | | | | | Joined: Nov 2012 Posts: 138 'Bolter | | 'Bolter Joined: Nov 2012 Posts: 138 | I know that the 40-52 three speed will tend to wear the third gear teeth and that will cause the transmission to pop out of gear. The wear is the tapering of one end of the gear teeth slightly. The solution is to replace the part but that part is becoming rare since it often needs to be replaced. I imagine the parts for your trans will be even harder to find. This blog below has a good picture and explanation. http://chev235guy.blogspot.com/search/label/Jumping%20out%20of%203rd%20gear | | |
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