Sectional view of gearbox

[Chris KC]

Smashing illustration Tony.

Since we all love a detour - my father worked as a mechanic at Hersham & Walton Motors at the end of the 1950's. Apparently at that time FWD Citroen transmissions were either costly or hard to obtain (I don't remember which). He maintained that whenever the HWM team crossed the channel it would come back with a few Citroen boxes in pieces and loosely described as 'racing spares' to any customs official who happened to look in the back of the truck! Every little helps as they say...

[Archivist]

Tony's work is to be applauded and yes, it would be nice to create a collection of these for the Archive. I would rather gather a collection of the magazines themselves, if possible, and have appealed in the past for such things.

Offers of donation, loan or sales are always welcomed. For example, Light Car and Cycle Car, Austin Advocate (and subsequent 'Magazine) plus original 'period' photographs are keenly sought...

[Mark McKibbin]

Hi Parazine
Somewhere I got the idea some Citroen had a sort of double helical bevel gear. Maybe I am dreaming but irecall seeing a set in a wreckers office 55 years ago.
The gears of the cruiser Belfast in the Thames can be seen. Because of their speed cruisers transmit very high power.

Apart from things like steering gears (for the Titanic) Citroen also used herringbone pattern gears for the crownwheel and pinion of his early cars up to about 1924 I think, Being Dutch he got the idea of the herringbone gear pattern from the wooden gears in windmills.  His innovation was to figure a way to make them in metal.

[Bob Culver]

Thanks Mike for a very impressive photo.They dont make things like they used to. Very curious as to how. Nor do they wear dirty overalls as they used to. I am also curious how such were ever cleaned!
Ironically the weak point of the Traction Avant was the cw and p!
As far as I know Seven synchro boxes give no serious trouble due failed thrust washers but many others do/did. The pieces going through the gears compound damage.

[Mark McKibbin]

Thanks Mike for a very impressive photo.They dont make things like they used to. Very curious as to how. Nor do they wear dirty overalls as they used to. I am also curious how such were ever cleaned!
Ironically the weak point of the Traction Avant was the cw and p!
As far as I know Seven synchro boxes give no serious trouble due failed thrust washers but many others do/did. The pieces going through the gears compound damage.

Yes the Traction has a very weak transaxle due in part to the fact it was meant to have an automatic transmission which as it was 1934 they could not perfect so at the last moment (I think 2 weeks) a manual was designed, unfortunately it usually takes the casing with it.  My traction has an ID19 motor and 4 speed transaxle just as should have come from the factory.

[Bob Culver]

Hi Mark
A colleague recently spent a lot of time rebuilding engine and gearbox of a very nicely restored L15 correcting wear and many assembly errors. All back together it transpired someone had fitted an early model replacement low ratio cwp so he had to take all the front end to bits again!

[Parazine]

As far as I know Seven synchro boxes give no serious trouble due failed thrust washers but many others do/did. The pieces going through the gears compound damage.

Sorry to disagree Bob, the thrust washers do wear in the Seven synchro box. Most boxes have too much endfloat in the layshaft due to worn thrust washers and the second/third speed gear thrust arrangement on the third motion shaft is also subject to wear. Both of these are quite difficult to repair and will cause sporadic jumping out of gear type faults if not fixed.

Usually caused by running with dirty, gritty, nasty oil during the "run them into the ground" years.

[Bob Culver]

Hi Parazine
If you can drive home or it does not deposit bits on the road, trouble is not serious!
Very many cars, possibly led by Ford from early 1930s, had loose thrust washers on the mainshaft. These break and the bits often wreck the rest of the box.

[Stuart Giles]

Thanks Mike for a very impressive photo.They dont make things like they used to. Very curious as to how. Nor do they wear dirty overalls as they used to. I am also curious how such were ever cleaned!
Ironically the weak point of the Traction Avant was the cw and p!
As far as I know Seven synchro boxes give no serious trouble due failed thrust washers but many others do/did. The pieces going through the gears compound damage.

Yes the Traction has a very weak transaxle due in part to the fact it was meant to have an automatic transmission which as it was 1934 they could not perfect so at the last moment (I think 2 weeks) a manual was designed, unfortunately it usually takes the casing with it.  My traction has an ID19 motor and 4 speed transaxle just as should have come from the factory.

And yet the Cooper T51 Formula one car used a (presumably much modified) Traction Avant transaxle in their World Championhip winning car. John Cooper may have moved on from Austin Sevens but was still a special builder I think.

[Mark McKibbin]

Yes I think the problem with the traction transaxle only manifests itself with a very worn crownwheel and pinion. The local club produces an internal reinforcing plate that holds the casing together, maybe Cooper bib something similar.