Gearbox product codes

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Sam Christie
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Re: Gearbox product codes

Post by Sam Christie »

I feel this thread ended well before its time even though it held out the hope of a comprehensive list explaining how to identify any gearbox likely to to be found in a Minor or an M-type (or on the garage floor).

I have been looking at identifying 4-speed gearboxes again and asking some questions on the Wolseley "Wasps, Hornets and Hornet Specials " Forum . I still feel the subject is utterly confusing and all the more so because some gearboxes are Morris, others are Wolseley and there is the odd real or alleged M.G. example too.

A contributor on the Wolseley Forum has commented that a key number to look at on a gearbox is what he calls the "Sanction Number" (a term I had not heard before). It is the number below the horizontal line in the picture below. If I understand him correctly the number '74' will only appear in this position on a Morris gearbox which, in this case is a 4-speed and almost certainly Minor (the J2 remote is not relevant).

Image


Image


The contributor also commented on the picture above (a synchromesh box which I guess is 1934 Minor- but you may know better) -

"I have a list of sanction numbers for several models of Wolseley in the early 30's and 110 is not one of them.Some models had more than one sanction number in any one year presumably to indicate a significant change."

He provided this Wolseley list which probably includes some gearboxes which would not fit a Minor -

Image

I think 3-speed boxes are fairly well understood but a 4-speed which fits an M-type can be Minor or one of quite a number of Wolseley permutations. Wouldn't a set of early 30's Nuffield gearbox catalogues be great?
Ian Grace
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Re: Gearbox product codes

Post by Ian Grace »

Sam,

Just checked the 4-speed crash box from my 1933 McEvoy - I believe it is the original. It is 9602/74 and behind the turret it has 3/12 - not the expected 4/17 speedo ratio. This may have something to do with the speedo and higher speed of the Model 70?
Sam Christie
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Re: Gearbox product codes

Post by Sam Christie »

The rear axle ratio might be another factor. The MG M-type and the MG D-type have the same gearbox and gearbox speedometer ratios but different speedometers because the D has a lower back axle ratio (heavier body?). The M-type has a PCN speedometer like the OHC Minor and the D-type has a PN. If you fit the lower ratio diff in the M the PN speedometer can be fitted and reads correctly - the combination has merit because the Smiths PN 0-80 speedometer is much easier to find (early Austin Tens used it) and the lower ratio crown wheel and pinion tends to be more easily found and much cheaper too.
Ian Grace
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Re: Gearbox product codes

Post by Ian Grace »

Very interesting.

I just checked my McEvoy speedo - it is the SV Minor type, of course, with the rotating disk. It is too corroded to see any numbers on it. Not sure how high it goes. And my back axle is inaccessibly buried in Tiger Moth!
Ian Grace
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Re: Gearbox product codes

Post by Ian Grace »

Here's the 1933 Hornet gearbox. The extract is from the Hornet Instruction manual, print date April 1933.

Unfortunately, the printers heavily touched up the photo, removing the numbers we're interested in!

Image
Ian Grace
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Re: Gearbox product codes

Post by Ian Grace »

And here's the earlier one-piece Hornet box. This taken from the Hornet Spare Parts List, print date August 1930.

Image
Ian Grace
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Re: Gearbox product codes

Post by Ian Grace »

Here's the SV speedo - 0 to 80 mph. This is the one I have obtained to replace the rusted out original.

Image
plj
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Re: Gearbox product codes

Post by plj »

Ian, The 4 speed synchro box fitted to my early s.v. has the no's 11593 over 110 at the front and the standard 4 over 17 at the back.

PhilipB
Trevor Wilkinson
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Re: Gearbox product codes

Post by Trevor Wilkinson »

The box on my 1934 two seater has a 51 sanction code. This confirms that it is a Hornet box. It is a four speed non synchro box and it doesn't have the handbrake mounting in the rear housing but has a bolt on carrier.
The gate is also reversed with 1st and 2nd where 3rd and 4 the would normally be.
I always thought you that it was a Wolseley box but nice to have it confirmed.
Image
Sam Christie
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Re: Gearbox product codes

Post by Sam Christie »

Philip the model number '110' with the speedometer ratio of 4/17 was common on Minors after the introduction of the synchromesh gearbox in 1934.

Trevor, your model '51' might have had a remote gear change in a Wolseley Hornet . Can you say what the speedometer ratio is please? I am in touch with a chap who has a '51' marked 4/14 and his has been fitted with a J2 remote.
Sam Christie
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Re: Gearbox product codes

Post by Sam Christie »

I have only just realised that we now have the answer to the question which started this thread. '51' is a Wolseley Hornet box.By the way because this gearbox probably started out with a Wloseley remote fitting a J remote is straight forward.

Image

I am starting to wonder if the code on the gearbox relates to the engine it was first fitted to. A list under the heading "Engine Numbers" published by the Triple-M Register in their "Register Current Issue 2013" at £8 plus £2 postage apparently quotes as engine model numbers the very numbers which I have assumed are gearbox codes. I hope this does not offend copyright but I was given this very blurred scan which gives some indication of the content -

Image

I am not sure if it is apparent how the system really worked or how it squared with a Minor having 4-speed boxes stamped '74' and '110' or MG J types having boxes stamped 72 and later 117. Similar questions on the Triple M Forum have produced almost nothing.

And here are the Wolseley numbers again (not all the same casing as the familiar J / Minor type) -

Wolseley Gearboxes

Nine 112,152
Wasp 177
Hornet 50,51,55,64,75,91,91A,107
12/Six 120
New Hornet (1936) 178
Hornet Special 65,78,114,163
14HP 156,181
16HP 58,76,115
18HP 158
21/60 84,85,116,133,139,161


Plenty of scope for confusion.
Last edited by Sam Christie on Thu Dec 05, 2013 2:33 pm, edited 1 time in total.
ian judd
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Re: Gearbox product codes

Post by ian judd »

Sam,
You have not noticed that the 'blurred scan' is the same document supplied (unblurred) by Ian Grace at the beginning of this thread! No wonder you thought you had seen it before.....

Ian
Sam Christie
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Re: Gearbox product codes

Post by Sam Christie »

Ah! Thanks Ian.I am afraid I had difficulty reading the scan the first time and skimmed it badly when I read "Engine Numbers" on a Gearbox thread. That will teach me to read things properly.

Image

All this relates to Wolseley derived gearboxes but I still do not understand how the MG 4-speed box was coded for the M-type. Is it also '52' like the D-type? The M-type note seems garbled to me. It reads, regarding the M -

MG**{first 27bhp engine was MG2024A{fitted to 2M2269}, first M-types to be so fitted was CM2193 and the first 2str was 2M2260}

Do they mean -

MG** First 27bhp engine was MG2024A (fitted to 2M2269), first M-types to be so fitted were Coupe CM2193 and Two seater 2M2269. (2M2260 should read 2M2269 as the start of the note says) .

I really should get a life but that first note confused me so much it further encouraged me to skim the rest of what is the best MG list so far. Did I miss a Morris list?
Trevor Wilkinson
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Re: Gearbox product codes

Post by Trevor Wilkinson »

Hi Sam, I haven't ignored your request re speedo ratio, just that the box is back under flooring and carpets. Will check next time it is uncovered.
Ian. Re your speedo. When I first got my Minor it recorded 1.1 miles for each mile traveled, I changed the innards for one I picked up, (no glass or face) and it corrected the reading 1:1
There are different odometer drive ratios within the speedos. :?
Ian Grace
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Re: Gearbox product codes

Post by Ian Grace »

Thanks for that Trevor. Other than 'MA' on these SV speedo's there doesn't seem to be any parallel with the 'PA', 'PC, 'PN', etc. seen on OHC speedos, so not sure how they can be distinguished, and this is why I thought perhaps that there was only one ratio. But then nothing in life in genral or with Minors in particular is ever that simple! The other impacting factor is that my gearbox appears to have 14/3 speedo gear ratio, whereas most Minors seem to have 17/4? So I'd be interested to survey speedo ratios in conjunction with the current (and fascinating) effort to sort out sanction numbers, and perhaps corrlate them with 'PA', 'PC, 'PN', etc., and with back axle ratios too? :o
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