A gearbox rebuild

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plj
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Re: A gearbox rebuild

Post by plj »

Ian,
I have acquired an early 3-speed box in poor condition which I will be dismantling for parts. The cross shaft looks sound albeit very rusty so providing I don't need it for my car you are welcome to it.

Philip
Ian Grace
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Re: A gearbox rebuild

Post by Ian Grace »

Thanks Philip!

Ian
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Re: A gearbox rebuild

Post by Ian Grace »

David,

Not sure exactly what you wanted to see. Here's the business end of the Derrington and the top of the box with the cropped lever that engages in the Derrington. Is that what you wanted?

The stub end of the cropped level engages in the universal joint inside the front of the remote. The remotre has a removable plate on the top so you can see to engage the two parts when assembling. There are four clamp bolts to secure the remote on the gearbox turret, and the round steel cap bolts down from the top to secure the remote onto the gearbox. Hope that makes sense.

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garagiste
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Re: A gearbox rebuild

Post by garagiste »

Ian,

Sorry I did not make myself clear, the part that interests me is looking down on the lever end of the extension.

Is there a plate with a slot to guide the lever into the 4 gears?

Thanks for the photos you have posted these will help me clarify the action of the item.

David.
Sam Christie
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Re: A gearbox rebuild

Post by Sam Christie »

May I add my thanks for these photos too? I am very keen to follow, step by step, the revelation of the inner workings of the four speed synchromesh gearbox and will watch with interest.

I could be mistaken, but I have the impression that some input shafts were produced for the MG J2 gearbox at one stage, possibly by Barry Foster, but the cost of doing this again would probably be too much.

The Derrington remote is interesting too - I do not recall seeing one previously other than in the illustration below - I note the highly polished finish -

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Ian Grace
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Re: A gearbox rebuild

Post by Ian Grace »

David,

Sorry about that - how's this?

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Your question led me to take a closer look at the remote - and, lo and behold, it appears that it should have a gate (referenced and visible in the advert), and mine, as you can see in this picture, is missing! Damn! But suppose it will still work without a gate? So I'll need to find another out there somewhere to copy the missing part. I'm not sure of the date of the Derrington advert, but it refers specifically to 3-speeds, but of course my box is 4-speed, so maybe they offered 4-speed-gated remotes at a later date? I don't know how rare Derrington remotes are - I had presumed that there would be others out there?

I also noticed that the gear knob has the four speeds and reverse on it. I had thought, for some reason, that when a remote is fitted, the gear positions become reversed front/back and left/right, but it isn't the case with this remote.

The other oddity is that period McEvoy literature suggests that McEvoy made their own remotes, so I was slightly surprised to find a Derrington on mine. The photo below is the remote on the Sarah Gibson McEvoy in Spain, which is quite different and may well be a McEvoy product. Has anyone ever seen anything like this? What a pity it is upholstered!

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Sam, this is a four-speed crash box, not the later synchro box.
ian judd
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Re: A gearbox rebuild

Post by ian judd »

It's only the J2 box which has the gear positions changed, though I don't know about Wolseleys. It looks like this remote will fit both a three and a four speed box, so possibly it was on a three and the gate was removed so that it would work a four. Presumably it's just a plate with the gate shape cut out - a bit like on the J2 tower.

On a completely different subject; has anyone ever seen, or actually got, examples of the special road springs in the Derrington ad?
plj
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Re: A gearbox rebuild

Post by plj »

Ian,
The ?McEvoy remote looks not dissimilar to a home made device I saw on a single seat A7 at Bromley PoM a couple of years ago. Unfortunately I can't locate the photos at the moment but if they turn up I will post them.
Ian Grace
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Re: A gearbox rebuild

Post by Ian Grace »

Ian,

I think you could be right. This could have had a 3 speed gate that was remove by McEvoy. The original gate may not have been wide enough for reverse. It should be perfectly drivable without a gate.

At least I now know that I should highly polish it!
Sam Christie
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Re: A gearbox rebuild

Post by Sam Christie »

In effect this may have been said already but - Since the Derrington remote cleverly adapts to the stub of the gearstick and clamps onto the gearstick mounting is it possible that it would fit both the 3 and 4 speed gearboxes? If this was the case, surely all that would need to change on the remote to adapt would be the gate pattern?

The remote on the Sarah Gibson McEvoy in Spain seems to use the stub of the gearstick too but why has it been upholstered?
Ian Grace
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Re: A gearbox rebuild

Post by Ian Grace »

That's right. And the thought is that if the remote was designed for a 3-sped box with an H pattern for 1, 2, 3 and R, then it might not have been possible to fit a gate with three rows of gears side by side. This could have been overcome by removing the gate, so the remote designed and advertised for a 3-speed box could be made to work on a 4-speed box. Just a theory. I could quite quickly attach the remote to the box and have a go changing gears and see where the lever ends up when in reverse.
Ian Grace
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Re: A gearbox rebuild

Post by Ian Grace »

This from David Hinds:

Hi Ian,

Attached are some shots of the remote controls that I have.

The standard MG one does not have a gate as such, however there is a restriction to stop it going too far back in 3rd (top). Very “clattery” due to worn bushes on the fore and aft part of the shaft.

The photo of your Derrington item seems to be far thinner (worn?) on the RHS than mine.

Awaiting someone to come up with a photo of the plate that is held in place by the four screws, is it just as the MG one?

There seems to be a range of modern remotes built up using rose joints.

Best wishes, David.

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Ian Grace
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Re: A gearbox rebuild

Post by Ian Grace »

Thanks David,

Yes, now I can seen that mine is well worn (or filed away?) on the right side, towards the rear, equating to the reverse gear position. So I suspect that these Derrington units were designed specifically for the 3-speed box, as advertised, and modifying the gate may not have left enough metal on the side of the gate, or the gate may even have precluded the lever from reaching reverse, so was simply discarded.
Jpallis001
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Re: A gearbox rebuild

Post by Jpallis001 »

Now while everyone is talking about gearboxes, from the photos below, can you tell me whether my gearbox is a synchromesh or non-sync gearbox? -- and, what should the end of the gearlever look like?
gearbox 1.jpg
gearbox 1.jpg (122.74 KiB) Viewed 4489 times
gearlever.jpg
gearlever.jpg (31.33 KiB) Viewed 4489 times
Sam Christie
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Re: A gearbox rebuild

Post by Sam Christie »

Well the thread is A gearbox rebuild . This looks like a synchromesh example to me. The aluminium casing for the non-synchromesh 4-speed is about 6" long but the synchromesh aluminium casing is about 7 1/4" .
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