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Finally ... Repairing a traction gearbox.

George 1/8th

Active member
If you fit the original riveted brake linings and properly centralise the shoes to the drums the brakes are excellent. The problem today is that people opt for bonded linings that are way too hard. My original 53 light 15 I had in 1966 was able to pull to a dead halt from 35MPH in 30 feet. They were always noted for having superior brakes to most other motor cars of the day. Sure pedal pressures are higher because the system is unassisted but highly effective in any case.
OMG white wall tyres?? How crass!
Gerry, you have to be kidding. Crass? It looked spectacular. They cost him a small fortune. They looked spectacular on the fully restored car.
 
If you fit the original riveted brake lining ...
Asbestos linings??? Possibly, later materials are simply harder due to the deletion of asbestos and require more pressure to give a similar effect. Why would being a bonded lining or not be significant? It would most likely be down to the pad material.
 

gerrypro

1000+ Posts
Yes definitely asbestos linings, but that is what they were designed for!
As for white wall tyres they are synonymous with the American hot rod scene! Then there is no accounting for peoples taste.
Back to the thread----- Shane I am eager to see just how the rebuild of the gearbox goes and what a difference it makes to the car.
People can make rubbish comments about Tractions as much as they like. It does not change the fact that they are one of the great cars of Automobile history and had as much influence as did the DS albeit 21 years earlier.
 

DoubleChevron

Real cars have hydraulics
Yes definitely asbestos linings, but that is what they were designed for!
As for white wall tyres they are synonymous with the American hot rod scene! Then there is no accounting for peoples taste.
Back to the thread----- Shane I am eager to see just how the rebuild of the gearbox goes and what a difference it makes to the car.
People can make rubbish comments about Tractions as much as they like. It does not change the fact that they are one of the great cars of Automobile history and had as much influence as did the DS albeit 21 years earlier.
Soon, I just need to get the car I'm driving back together. The most obvious faults are the gear missing teeth ( photographed ) and considerable slop in the reverse idler gear.
 

gerrypro

1000+ Posts
You will also need to reset the C W and P once it has been disturbed. It is necessary to remove the Diff in order to extract the main shaft. Whilst the pinion and main shafts are out it is good to replace the double row front bearings. Replacements are 3305s and used to be very commonly available from local bearing service shops. The rear pinion bearing is a little harder but being a roller bearing give very little trouble. The very hard bearing to source is the Thrust bearing on the pinion shaft between second fixed pinion and the first/ reverse cluster gear. The reverse idler may not be as critical as you may think The bronze bush ids by design a loose fit to allow lubrication and the ball thrusts at each end can be refurbished merely by reversing the thrust rings to eliminate excessive end play!
Of critical importance is the condition of the half locking rings and if too far gone to be cleaned up by lapping must be replaced. This will definitely involve re-shimming the adjustments for conical depth of the pinion!
 

DoubleChevron

Real cars have hydraulics
You will also need to reset the C W and P once it has been disturbed. It is necessary to remove the Diff in order to extract the main shaft. Whilst the pinion and main shafts are out it is good to replace the double row front bearings. Replacements are 3305s and used to be very commonly available from local bearing service shops. The rear pinion bearing is a little harder but being a roller bearing give very little trouble. The very hard bearing to source is the Thrust bearing on the pinion shaft between second fixed pinion and the first/ reverse cluster gear. The reverse idler may not be as critical as you may think The bronze bush ids by design a loose fit to allow lubrication and the ball thrusts at each end can be refurbished merely by reversing the thrust rings to eliminate excessive end play!
Of critical importance is the condition of the half locking rings and if too far gone to be cleaned up by lapping must be replaced. This will definitely involve re-shimming the adjustments for conical depth of the pinion!
I'll have to read the manual, and try to understand all of this :) I'm sure it is obvious one the shafts are out !

seeya,
Shane L.
 

lhs2.1

New member
Hi Shane,
back in the '70s and '80s I rebuilt quite a few TA gearboxes.
I wrote up how to dismantle, examine, and re-assemble them at the time. The file will tell you all you need to know, but it's 4MB. If you pull the synchro hub apart cover it with rag to stop all the bits flying about. You will need the special tool to put it back together which I have.
I'm seriously ill at the moment but if you wish to have the file and borrow the tool(s) ring Fay on 5472 3130
roger
 

pug206gti

the famous 18E
The only time one needs to double clutch is changing from 2nd back into first whilst on the move. Thankfully this is never really needed as 2nd is a good strong gear and can haul away from very low speeds. BTW have you ever needed to drive a D with a broken clutch cable? One starts the car with 1st engaged and then it is rev matching to accomplish all changes from then on once moving!
G'dday,
no, but I have driven a 2½ Riley with a broke clutch rod, a common occurrence if it is not adjusted correctly.:cool:
 

jonf

Member
i have a spare TA gearbox and engine unit if anyone wants or needs it.... what is going price in 2016? Engine seems complete. gearbox was known to be a good box when last installed in a car back when T Rex roamed the surface of Terra Australis, a different TA. i am in inner city Melbourne, 0407 807 813 jon
 

DoubleChevron

Real cars have hydraulics
Hi Shane,
back in the '70s and '80s I rebuilt quite a few TA gearboxes.
I wrote up how to dismantle, examine, and re-assemble them at the time. The file will tell you all you need to know, but it's 4MB. If you pull the synchro hub apart cover it with rag to stop all the bits flying about. You will need the special tool to put it back together which I have.
I'm seriously ill at the moment but if you wish to have the file and borrow the tool(s) ring Fay on 5472 3130
roger
An incredibly generous offer. Concentrate and getting yourself better and we'll worry about cars later :) ..... This stuff can always wait !!! (hey this one has waited 15years so far!!).

seeya,
Shane L.
 
i have a spare TA gearbox and engine unit if anyone wants or needs it.... what is going price in 2016? Engine seems complete. gearbox was known to be a good box when last installed in a car back when T Rex roamed the surface of Terra Australis, a different TA. i am in inner city Melbourne, 0407 807 813 jon
Put it away as a spare for your new (old!) traction Jon. Never know when you might need it.
Dave G
 

Exfrogger

1000+ Posts
A friend of mine restored one of those many years ago. He let me have a drive of it. He had fully restored the car , the engine, everything. It was a truely HORRIBLE experience. No synchro in any gear. You had to double clutch it, it was just no fun at all. I'd be taking those cogs out and replacing them with something user friendly.
Something at least with synchro mesh.
Aint nought but a Big Girls Blouse...

A red-blooded, hairy-chested, Australian bloke would not notice wever it had synchro or not.

In fact he'd drive a modern manual but use the clutch under duress. And, on the rare occasions he does gnash the gears, he calmly states in a loud voice to anyone with in earshot, "T'aint no point in having teeth if'n ya don't clean them!"
 

gerrypro

1000+ Posts
Hi Shane,
back in the '70s and '80s I rebuilt quite a few TA gearboxes.
I wrote up how to dismantle, examine, and re-assemble them at the time. The file will tell you all you need to know, but it's 4MB. If you pull the synchro hub apart cover it with rag to stop all the bits flying about. You will need the special tool to put it back together which I have.
I'm seriously ill at the moment but if you wish to have the file and borrow the tool(s) ring Fay on 5472 3130
roger
Hi Roger, I am truly devastated to hear that you are not well. Hang in there old friend and do the best you can to get well.
 

gerrypro

1000+ Posts
But I do understand. I can see the synchro. It's a half-girlie car; there are 1st and 2nd to master. In other prewar vehicles there might be 3 or 4 as well.
My father had a Lancia Lambda. They had a four speed non synchro box. Once double clutching and rev matching for the upward shifts was mastered the box was silky smooth to drive. The sheer delight of mastering the technique was a joy in itself. Dad reckoned he could play a tune on that box!
Sadly I was never able to try it for myself. The car was long gone by the time I was old enough to drive!
 

gerrypro

1000+ Posts
A friend of mine restored one of those many years ago. He let me have a drive of it. He had fully restored the car , the engine, everything. It was a truely HORRIBLE experience. No synchro in any gear. You had to double clutch it, it was just no fun at all. I'd be taking those cogs out and replacing them with something user friendly.
Something at least with synchro mesh.
George it occurred to me that the reason that you clashed the gears and hence spoiled your driving experience may have been the old trap that newbie traction drivers often fall into. The synchros in a TA box are slowish compared to modern cars. They are never going to be quick even when brand new. Hurry the change and they will clash every time. The technique is a definite 123 action.
1 being the release from the current gear, 3 being the selection of the next gear and most importantly 2 being a defined pause in the centre of the gear change gate. This allows time for the bronze synchro cone to bite on the forged steel cone of the idler gear and then the outer synchro drum that is internally splined can accurately lock over on to the dog teeth of the idler gear. Follow this practice and driving a TA becomes a refined and delightful experience.
Nothing on the road steers as directly and accurately as a TA. Although heavy at parking speeds it is quite manageable as long as the wheels are slowly rolling. On the open road the steering comes into its own and is well weighted. The cars were renowned for their strong and progressive brakes and for a drum system were comparatively resistant to fade. The handling is ideally balanced with a 55% weight bias on the front wheels (the optimum figure for front wheel drive ) and one can cruise all day at 55 to 60 miles per hour in comfort. This was of course ideal in its era of narrower winding single lane roads common in most parts of Europe and England, even here in Australia our major highway, the Hume was only one lane in each direction and on the NSW side appallingly maintained. Todays freeways do not suit the car well at all. That being said on a recent run to Shepparton up along the Goulburn Valley Highway I was able to hold speed with the traffic a 110KPH. The engine was certainly working at its maximum and at those speeds the noise levels become a little overwhelming for normal conversation!
 

DoubleChevron

Real cars have hydraulics
add some files I"ve stolen from the TA group. Yes, Gerrys work too :) Sadly Roger Brundles rebuild document seems to have gone walkabout ( there is a directory there but no file in it).
 

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DoubleChevron

Real cars have hydraulics
Reconditioning the gearbox in my 1955 Traction.
Richard Sheil
Dublin, Ireland

Introduction:
As some of our members may know my car broke down fairly significantly during last year’s Annual Rally in York which necessitated an engine rebuild. However I had noticed that the gearbox had become rather noisy and so decided to recondition it too during the winter of 2006 / 2007.

Having never done this before to any car I began to realise that there was a fair bit of mystery attached to the Traction gearbox and set about understanding what was required. These notes are a description of what I did to my gearbox and I am sure more experienced people may have some other views. They also don’t describe every action but are written from the point of view of what I would have liked to have known before starting out on this project.

The manual that I have is very clear in listing each step of activity required. What it lacks is a clear overview of what the steps are trying to achieve. Without the overview I think you are operating blind.
Objective:
In my view the objective of the gearbox overhaul is to replace all bearings and bushes, inspect and replace gears and shafts etc as necessary and to set clearances to specification.

I have modified the drawings from the parts books to reference the numbers that are used in the manual. This made it easier to ensure that the correct parts were reinstalled correctly and to understand what is going on.




Having disassembled the gearbox to its constituent parts and having cleaned them and laid them out in order on the bench the objectives are:
To set the second gear axial play (between 34 and 21 on Gears drawing) to between 0.05 to 0.10mm by choosing the thickness of the celeron washer (36).
To set the 3rd gear axial play (between 3 and 38 on Gears drawing) to between 0.10 and 0.20mm by adjusting the thickness of washer (49).
To set the play between the 1st gear (40+12) and the bearing on the pinion shaft to between 0.10 and 0.20mm by choosing the thickness of the celeron washer (39).
To set the play for the reverse / first idler to between 0.05 and 0.20mm.
o remove as much backlash from the planet gear / satellite gear assembly of the differential (see Differential drawing) as possible by setting the position of the satellite gears correctly by means of the adjustment washers.


To preinstall the pinion shaft in the gearbox followed by the differential and to set the axial position of the shaft such that the clearance between the end of the shaft (pinion end) and the differential housing is to specification, this is known as the pinion to crown wheel setting. This is done by means of the metal shims (see Differential drawing). The specification is engraved on the end of the pinion and on the crown wheel.
Once these settings have been achieved the gearbox is reassembled and the pinion to crown wheel setting checked once more.
To set the tangential or rotary play or backlash of the pinion to crown wheel to specification. The manual says that this setting is engraved on the crown wheel but this was not the case. In my case by asking the question on TA-L discussion group I was able to determine the specification to be between 0.19 and 0.23mm.
To verify that with the complete gearbox reassembled that the synchromesh unit overlaps third gear when third is selected and second gear when second is selected. In the event that this is not correct then the axial position of the whole primary shaft may be adjusted by means of paper shims (see Casing drawing)


Disassembly:
Disassembly of the gearbox is relatively straightforward if the manual is followed. In my case I discovered the following. I broke the casting supporting the reverse gear idler shaft as I tried to drive the shaft out with a punch. If I had extracted the plug which inhibits removal of this shaft by pushing it in toward the gearbox this would not have happened. I also found all gears to be in excellent condition. The differential had large play caused by the crown wheel not being properly fixed to the differential housing and by significant wear in the planet / satellite gear area. Given that I was going to reset everything to factory settings I did not measure the existing settings but others may wish to do so for completeness. The large nuts on the end of each shaft were removed using a large socket. To do this the gearbox must be stopped from rotating and this is done by selecting 3rd and 1st gear at the same time.

Replacement:
I replaced all the bearings in the box. The only quirk worth noting is that the rear bearings for the primary shaft were not available and instead of replacing two bearings with a spacer between them, a single bearing was used, held in place with circlips. In my case I had to grind down one of the circlips by a small amount to allow both clips return into their associated grooves in the shaft.
I replaced all the bronze bushings in the gears as they were allowing each gear to rock slightly in relation to the shaft. I replaced bushings in gears 18, 35, 40 and the reverse / first idler. A hydraulic press is needed to carry this out and the bushing in gear 18 had to have oil holes drilled once installed. The bushing in gear 35 consists of two bushings which are pressed in from each end. I understand that they can have a tendency to migrate towards the centre of the gear so I installed them with Loctite Bearing Fit.

Reassembly of the Differential:
This was quite fiddly as it was necessary to repeatedly trial fit each satellite pinion and washer to the cross shafts in the differential to determine the correct washer thickness for each satellite pinion (see Differential drawing). Once this was done the whole differential was then reassembled repeatedly with different thickness celeron washers behind the planet gears to until minimum backlash but no binding was achieved. In my case the satellite pinion washers were not available in the thickness that I required so I compensated for this by increasing the thickness of the washers behind the pinions to tighten the mesh.

I used new bolts to clamp the crown wheel to the differential housing and fastened them with lock tabs and Loctite.

Setting axial clearances on shafts:
Parts 34 to 21 were reinstalled on the primary shaft and held in place with the locking pin and spring that can be seen on the Gears drawing. This was done with the shaft removed from the gearbox. The pin and spring were reinstalled using some grease to stop them flying across the workshop and a bent piece of wire to push them home. I used a pop rivet with the end bent at 90 degrees to make a think hook. The thickness of the washer 36 (made of fibre like material called Celeron) was chosen to make the required clearance as listed above. In my case having bought washers in myriad sizes I still did not have what I required so had to adjust the thickness of the washer by rubbing it on a flat surface with emery paper. Once again this was a case of multiple trial fittings until a suitable clearance was obtained.

The third gear axial play was checked between 3 and 38 and found to be acceptable. If it was not then the steel washer 38 would have had to be ground to size.

The pinion shaft was also assembled on the bench and when fully tightened the clearance between 39 and the bearing checked. I am confident that the part listed as 51 (see Gears Drawing) does not exist on late gearboxes. Once again the celeron washer 39 had to be made to the required thickness on the emery paper.

I measured the reverse / first idler play. It was more than the specification but as I had no means to change it and as the bearing races and hardened washers had no evidence of wear I deemed the settings not to have changed since the gearbox was first built. On consideration I was confident that this was one of the least important clearances in the box and reassembled it unadjusted.
Reassembly:
The pinion shaft was then disassembled and reassembled into the gearbox casing. The differential was reinstalled to the casing with the ring nuts tightened fully (see Differential drawing) so that there could be no wobble of the differential housing relative to the casing. In my case the number etched on the pinion and crown wheel was 56.70mm. Given that the diameter of the housing is 55 mm this indicates a clearance of 1.70mm between the end of the pinion and the housing. This was then set by means of multiple trial fittings of punched metal shims between the bearing housing and the gearbox casing. I did not install the cover over the bearing housing and discovered to my disappointment that the pinion could move towards the front of the box thus making all my work void. I then repeated the task with the cover on the housing to achieve the correct clearance.

Once that setting was completed the differential was removed and the reverse and primary shafts reinstalled in the box. The reverse shaft was refitted before the primary shaft. The primary shaft was installed paying particular attention that the synchro key (37) was engaged firmly between washers 34 and 38. If this was not done correctly it would chew itself to bits in moments. Apparently this is a common failure mode of these boxes if the nut on the end of the primary shaft becomes loose. I used Loctite on both nuts on the end of both shafts to reduce the chances of this happening. I also tightened the nuts as tight as I could using an extension bar on the socket drive and a wooden pole wedged into the gearbox housing to provide leverage.

Once all gears were reinstalled the differential was refitted. The axial clearance was rechecked.

The ring nuts on each side of the tapered differential bearings were adjusted successively so as to bring the crown wheel into mesh with the pinion. A dial indicator was then used to check that the free rotation of the crown wheel was between 0.19 to 0.23mm at the outer diameter of the crown wheel. This was done with the pinion stopped from rotating by a block of wood so that the movement was purely the play between the meshing teeth at the pinion to crownwheel.

Once this was achieved the ring nuts were backed off slightly to allow the play required by the tapered bearings.

With all of these settings rechecked the top cover of the gearbox was reinstalled temporarily. The selectors were activated so that third gear was selected. The cover was then removed and it was determined that the synchromesh unit overlapped the teeth of third gear. This same test was repeated for second gear. With the unit overlapping third gear when pushed forward and second gear when pushed rearwards I was confident that the axial location of the primary shaft was acceptable. There is a more complex procedure in the manual but after careful consideration I was confident that this was enough.

Testing:
I reinstalled the box in the car together with the newly rebuilt engine and took the car for a drive. Sounds easy! Once I got over my fears that the whole thing would grind to a halt I was amazed at the difference in feel. The gear change was more positive and while it is early days I am confident that the overall noise level and howling from the differential are much reduced. It just feels a whole lot more pleasant to use.

Conclusion:
I would recommend anybody with some mechanical experience and the limited special tools (dial indicator and feeler gauges) to take this on. You won’t regret it.

Finally I would like to thank the people on the TA-L discussion group as they were a wonderful sounding board for me and provided guidance every step of the way.diag2.jpgdiag1.JPG.jpgdiag3.jpg
 
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gerrypro

1000+ Posts
Hi Shane, I am glad you found that, and that Richard took the time to document his work. I corresponded with him on a frequent basis through the TA-L Yahoo group when he was undertaking his rebuild.
 
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