Classic cars forum & vehicle restoration.

[petelang]

I'm hoping some of the pre war chaps on here can proffer some advice as regards to suppliers who can overhaul and repair preselect gearboxes.
I have contacted one very well known specialist who just about gave me a heart attack estimate of somewhere north of £5,000 up to £10,000!
I'm in East Midlands Region but there seems to be no one around here. A rumour that there is somebody in Exeter and I have posed the question to the Riley club spares people may have suggestions.
Has anyone had a go themselves? Is it really scary engineering, needing a whole bunch of special tools and facilities?
Surely, its not like rocket science as this stuff was made in the 1930s?
Peter
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Daimler Fifteen 1934
Armstrong Siddeley 15 Long 1933
Daimler V8 250 1969

[Ray White]

Pete. If I were in your shoes I would have a go at sorting the pre selector gearbox myself. No, I have not done one myself ( my Dad would have got stuck in but sadly he is no longer with us) but I would read up on it first. The problem with the Wilson box was usually adjustment of the bands and I don't think it is exactly complicated - not in the way an automatic box is - but it is different to what we are used to.

I believe there is quite a bit of useful information available on line but if you get stuck I can search through my old motor repair books. OCC has some info.

https://www.oldclassiccar.co.uk/library/wilsonpreselector.htm

[Minxy]

It’s the same box used in the Lanchester so you could have a look at DLOC forum or Google Lanchester and see if any links come up.

I believe in general most faults, on Lanchester anyway, are down to oil levels in box and/or flywheel or simple adjustments.

I do have a copy of the repair manual but have no way of copying it. You are welcome to borrow it if it can be arranged but I would need it back as although it’s a copy itself I’m told it’s still scarce.
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Hillman minx convertible. Lanchester LD 10

[Ray White]

I think the clever way in which the pre sector box works - with epicyclic gears and self adjusting brake bands - means you never need worry about worn gear teeth or bearings. The loadings are so light that a very high trouble free milage could be assured.

I think the biggest risk comes from the box being mistakenly dismantled... or run with low oil levels.

[petelang]

Minty, thanks for commenting. Owning a Daimler 15 too I know the principles but the early Siddeley box is a big animal and doesn't resemble the Daimler/Lanchester types.
Information on pre war Siddeley stuff seems scarce and as this car is reckoned to be one of very few survivors, chance of finding anyone familiar with this model are virtually nil.
On the positive side though, these Wilson boxes are generally very tough and durable (as is most Armstrong Siddeley stuff!).
I have never had a gearbox in bits myself and I'm very nervous about meddling at my age with the unknown, but if I could enlist someone with experience in the field it might be less fearful.
The other great difficulty is parts and a specialist is of course, more likely to be able to source, or make bits. I know I could get bands relined but they usually require bedding in on test and I don't have a test facility either.
As this unit is a complete unknown, I could take it apart and find all manner of insurmountable problems. It's a bit like Ray with electrics....Scary stuff!
When I was in management in the bus industry, my team overhauled bus transmissions for Routemasters and more modern epicyclics and an awful lot of special tools we're involved in measuring and setting up geartrains and naturally I don't have much more than a basic bodgers tool kit so this is another worry.
I had the covers off on the side of the box to have a look and observed some strange arrangements for springs associated with the shift busbar and cam arrangement. It just didn't look right but without an exploded view or any form of manual it's impossible tell if this is someone's prior bodge or if that's how it should be.
I went back at the supplier who quoted and they say they will assess it for much lower cost but if I end up getting back a crate of dismantled bits, and no knowledge how to fix it I would have virtually scrapped my only chance of a replacement spare gearbox.
It's a dilema!
I need a "Ray's Dad to step forward, no disrespect Ray. He sounds like just the sort of guy I would have got on with.
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Daimler Fifteen 1934
Armstrong Siddeley 15 Long 1933
Daimler V8 250 1969

[petelang]

https://flic.kr/p/2nfQY5f

https://flic.kr/p/2nfWrou

https://flic.kr/p/2nfWfpJ

A few images so you can see what I'm looking at.
First view shows side cover removed. The busbar that does the shifting is within here. A camshaft acts on the inboard side of the leaf springs to allow the gear required to be selected. The actual movement of the cam stroke is minescule. I'm particularly concerned about the strange attachment of those coil springs. Doesn't look right to me?

Another view shows selector levers at front of the box. Within this cover is a lever arm and a clevis pin working a lever within the box which moves the camshaft on the opposite side of the box. Looking at front of the box, reverse would be fully rotated clockwise, top gear fully anti clock.
Top cover removed shows band adjusters. The Reverse arrangement looks complicated towards rear of the box.
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Daimler Fifteen 1934
Armstrong Siddeley 15 Long 1933
Daimler V8 250 1969

[Ray White]

[Ray White]

I am intrigued by the "lollipop" sticking out the end of the box? (photo 1).

Also, it all looks like new in there...unless you cleaned it... I would suggest it is a recon box.?

[petelang]

Ray, do you mean the big ball mounting on the front? It has two hemispherical clamps attaching it to the crossmember forward of the gearbox. Back end is a torque tube, no rear mountings as such but twin stabilising rods to rear outboard axle mounts. It's a very heavy lump to just be suspended in such a way but its been there 89 years so I guess you might say it's pretty successful.
I must say, when I took the lid off I thought the same but as I've no way to test it statically it's anyone's guess. Who knows what might lurk inside the geartrain or the bands, although none of them are rattling about inside.
I know Routemaster gearboxes in London buses took collosal punishment before anything actually broke so I'm crossing fingers and toes...
Peter
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Daimler Fifteen 1934
Armstrong Siddeley 15 Long 1933
Daimler V8 250 1969

[Ray White]

Thanks for explaining, Pete.

It seems you need a means of rotating the box to see if the pumps are (both?) working and if the selector mechanism is O.K. I wonder if a stationary engine would do the trick.?

They used to be cheap as chips at one time but now they are being collected I don't suppose they still are.

I suppose you could start by attaching the pedal and seeing if it does anything. Does the pedal hydraulically pressurise the oil?

[alastairq]

[petelang]

I don't think there's anything hydraulic about the mechanism Ray. It's just linkages and a bl**dy great big spring involved. The big spring is compressed by the "change speed pedal" to effect a shift, hence if you get it wrong and end up in a "false neutral" the pedal comes back under your foot with all the force of an ejector seat!
Looking at this unit has given me some fresh thoughts about a problem with the original box presently serving in the car (subject of another recent unsolved query on here) which has a queer foible and sometimes won't pick up reverse (usually when on a slight forward slope facing a wall or, where it can cause me the most acute embarrassment).
The flat leaf springs seen in the side window are pushed from behind by the small camshaft and in doing so allows the one in engagement to have the spring force applied to it to lift the brake band operating rod and hence tighten its grip on the rotating planet drums.
I wonder if, in the case of reverse selection, if the camshaft is worn and not moving the leaf spring sufficiently to allow movement of the mechanism but its conjecture until someone "in the know" could pass judgement on my theory. Either that or I've got some lost motion on the rod from the selector on the right of the box to the camshaft lever but I would have thought this might affect other gears too.
Sorry for my thinking out loud but it's getting frustrating not knowing exactly how the internals work. If I do send it to the VERY expensive specialist I shall be sure to go and see it in bits as that is truly the way to understand how it works and what might go wrong.
_________________
Daimler Fifteen 1934
Armstrong Siddeley 15 Long 1933
Daimler V8 250 1969

[petelang]

I don't think there's anything hydraulic about the mechanism Ray. It's just linkages and a bl**dy great big spring involved. The big spring is compressed by the "change speed pedal" to effect a shift, hence if you get it wrong and end up in a "false neutral" the pedal comes back under your foot with all the force of an ejector seat!
Looking at this unit has given me some fresh thoughts about a problem with the original box presently serving in the car (subject of another recent unsolved query on here) which has a queer foible and sometimes won't pick up reverse (usually when on a slight forward slope facing a wall or, where it can cause me the most acute embarrassment).
The flat leaf springs seen in the side window are pushed from behind by the small camshaft and in doing so allows the one in engagement to have the spring force applied to it to lift the brake band operating rod and hence tighten its grip on the rotating planet drums.
I wonder if, in the case of reverse selection, if the camshaft is worn and not moving the leaf spring sufficiently to allow movement of the mechanism but its conjecture until someone "in the know" could pass judgement on my theory. Either that or I've got some lost motion on the rod from the selector on the right of the box to the camshaft lever but I would have thought this might affect other gears too.
Sorry for my thinking out loud but it's getting frustrating not knowing exactly how the internals work. If I do send it to the VERY expensive specialist I shall be sure to go and see it in bits as that is truly the way to understand how it works and what might go wrong.
The picture here shows a similar camshaft arrangement.
https://flic.kr/p/2ng2kdj
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Daimler Fifteen 1934
Armstrong Siddeley 15 Long 1933
Daimler V8 250 1969

[petelang]

This shows the working bit Ray.
https://flic.kr/p/2ng17mw

Alastair, that made me laugh.
No wonder some of the units we took to bits were considered BER! Beyond economical repair. By far the most popular failure of RM boxes was where the LT semi skilled service guys put the wrong oil in and they came apart with a thick coating of baked on shellac on everything and how they ever remained driving until this stage we never understood.
_________________
Daimler Fifteen 1934
Armstrong Siddeley 15 Long 1933
Daimler V8 250 1969

[Ray White]

Pete. Have to ask, have you tried loosening the lock nut and turning as adjuster 1/4 turn on the reverse gear band?

I just can't see the cam on reverse wearing like you suggest. It doesn't get enough use, surely.