Gear selectors, urgent advice needed

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Gear selectors, urgent advice needed

Postby Alice » Fri Jan 20, 2017 3:10 am

Who can let me in on the correct method / sequence to refit the selector forks onto the 3 rods in the gearbox top (1929 3 speed).
I have pics of the correct rod/selector placement, but as with all such beasts there is a trick to getting the detent balls fitted. In this case this is specially relevant to the 2 balls which appear to take turns sitting in a hole in the central rod.
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Re: Gear selectors, urgent advice needed

Postby Ian Grace » Fri Jan 20, 2017 3:40 pm

Hi Barry,

Peter Hills has recently done a complete rebuild of his 1929 gearbox and he wrote it up for the last magazine. I'll e-mail him to get in touch with you and talk you through the re-assembly of the selectors. He will also probably have photographs.

Good luck!

Ian
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Re: Gear selectors, urgent advice needed

Postby Alice » Fri Jan 20, 2017 11:03 pm

Ian,
I was busy working on gearboxes, taking photos along the way, when my wife brought the mail in, including the latest mag.
Amazingly there was the article describing what I was doing, and with almost identical pictures!
The only bit missing was the selector info, so I will look forward to hearing from Peter.
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Re: Gear selectors, urgent advice needed

Postby Ian Grace » Sat Jan 21, 2017 4:00 pm

Barry,

That's hilarious! Only sorry it took so long for the Oz magazines to be delivered - I was hopeful that they would be with everyone in time for Christmas.

I have e-mailed Peter and asked him to respond to this thread so that we can all benefit from the knowledge.

Ian
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Re: Gear selectors, urgent advice needed

Postby PeterWHills » Sun Jan 22, 2017 2:30 pm

Hi Barry
I did not disassemble the gear selector assembly on my 29 Minor with 3 Speed gearbox. See additional pictures showing the top cover from plan and side view. Refitting the balls would I imagine would be achieved by using a dummy rod. I think you could use the 'centre' rod as it does not seem to have groves and locking balls. I assume the balls are spring loaded so you will need to fit one at at time, secure them with the dummy rod then fit with the actual rod push the 'holding rod' out so that eventually the correct rod takes it's place. I hope I have described this clearly and that it works!

Setting the selector positions to align with the associated slots in the actual gears took several tries. When you believe you have it the selector cover in place (ignore the band brake connections) just nip it down and check that you can select the gears.

I hope this helps.
Peter
Attachments
20160723 Gearbox Gear Selector - DS9936 - 1929MM4 Seat Tourer July16 PH3_3077c.jpg
Close up of Gear Selector Rods
20160723 Gearbox Gear Selector - DS9936 - 1929MM4 Seat Tourer July16 PH3_3077c.jpg (378.46 KiB) Viewed 472 times
20160723 Gearbox Gear Selector - DS9936 - 1929MM4 Seat Tourer July16 PH3_3076c.jpg
Plan view of Gear Selectors
20160723 Gearbox Gear Selector - DS9936 - 1929MM4 Seat Tourer July16 PH3_3076c.jpg (361.47 KiB) Viewed 472 times
20160706 Gear Box Main Gears on Selector Top Cover - DS9936 - 1929MM4 Seat Tourer PH3_2991c.jpg
Side View of Gears on selectors
20160706 Gear Box Main Gears on Selector Top Cover - DS9936 - 1929MM4 Seat Tourer PH3_2991c.jpg (375.17 KiB) Viewed 472 times
20160706 Gear Box Main Gears on Selector Top Cover - DS9936 - 1929MM4 Seat Tourer PH3_2989c.jpg
Plan View of Gears on Selectors
20160706 Gear Box Main Gears on Selector Top Cover - DS9936 - 1929MM4 Seat Tourer PH3_2989c.jpg (341.33 KiB) Viewed 472 times
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Re: Gear selectors, urgent advice needed

Postby martinng » Mon Jan 30, 2017 12:13 pm

Peter, I also thank you for your magazine write up and the pictures of the gear shaft. These provides the clearest view yet of the assembly.
I still have a gearbox to re-build but have been a bit nervous without quite knowing what to aim for.

I did disassemble a gear selector and after I realised that there was a locking plate to hold the selector rods in position the selector rods could be pushed out once it had been removed. This has to be done carefully as at this point the indent balls and springs will come loose. Care needs to be taken not to have them ping out and get lost. I did discover that S&V can provide replacements for those that do disappear in the garage during the process.
I reckoned that the really difficult bit would be the replacement of the indent balls and springs and I had come to the conclusion that a dummy rod would be required as you suggest and presumably kept very tight up against the real shaft to prevent the balls falling between the gap! I still have to complete this operation.
I also remember that it is important of course that the selector spacers (which are of different lengths) are kept in the right places on the rods.

I took the selectors (a spare set) apart to see how they worked as I had a gear selection problem. This turned out to be nothing to do with the selectors, but a worn tip on the gearlever. This wear allowed the gear lever to move across the selectors before the box had been returned to neutral, thus locking up the selectors. The thread
viewtopic.php?f=6&t=1216&hilit=gear+lever#p8597
gives additional information on gearbox rebuilding and ends with my reshaping of the gear lever tip, which works to this day.
Attachments
Reworked lever 3vs.jpg
Reworked gear lever
Reworked lever 3vs.jpg (85.29 KiB) Viewed 466 times
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Re: Gear selectors, urgent advice needed

Postby garagiste » Mon Nov 13, 2017 8:08 pm

On the centre rod, at about the mid point there is a hole to carry a ball(s).

Should there be one or two balls in this hole?

Assume there is no spring
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Re: Gear selectors, urgent advice needed

Postby PeterWHills » Mon Nov 13, 2017 8:23 pm

I think you mean the central semicircle slots in the central rod, they are where the gear lever fits. If there is a ball it should have a spring.
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Re: Gear selectors, urgent advice needed

Postby Alice » Tue Nov 14, 2017 1:21 am

There are two balls that live in that hole, and no spring. However they cannot both be in there at the same time when all is assembled (no room for two). When everything is assembled properly there is one ball half in and half out, lining up with one of the circular grooves in one of the outer rods. The purpose is to prevent engagement of more than one gear at a time.
I made up a dummy rod for fitting balls and springs into the selectors, but still a tedious task! Getting the balls into the centre rod was a real pain, and several times when I thought all was OK I found that one had fallen out into the bottom of the box. You have to line up a selector groove and the centre hole so you can drop the balls in. This means having to rotate the centre rod during the process, and that's when a ball can fall back out if you're not careful. Pleased to say my rebuilt box now seems to work perfectly (on the bench, since there's no running car to put it in).
Have fun with your job!!
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