Stalwart Transmission

[madrat]

Hi, I'm considering purchasing a stolly and had a question about the transmission! I understand the 'wind up' problems and wondered if it was possible to remove 4 of the propshafts connecting the bevel boxes in order to make it into a 6x2 for road use?

 

Does anyone have a diagram of the transmission layout?

 

Many thanks in advance,

 

Duncan

[ArtistsRifles]

I "think" its been done - best bet though is to go to http://groups.yahoo.com/groups/stolly/ and do a quick search of the messages there. Also take a look through the image archives.

 

FWIW 4WDonline.com published this simplified image a while ago - not sure if it's of any use to you:

 

To be honest though it's eally a lot of work for nothing -all you'll really do is ruin the vehicles off-road abilities as, at todays fuel prices, you can't afford to drive it on the roads far enough for wind-up to be a serious problem. A Stalwart won't do more than about 2.5 mpg.

Edited July 2, 2008 by ArtistsRifles

[Stormin]

Duncan

 

I think you'd have to be careful about the amount of torque you'd be putting through just two driveshafts and hub reduction gears.

That torque is multiplied quite a large amount by the gearbox and bevel boxes and is usually shared by six sets of drive components not two!

You could well find you just destroy the bits that are connected all the quicker and as Neil says lose the off road ability.

From what I have read on the Yahoo forum's consistency in tyre circumference seems the most critical item to avoid wind up. Something Jimmy owners should also be familiar with!

P.S. if your getting bored of the Scammell I could be interested

Norman

[ArtistsRifles]

Good point on tyre circumference Norman!!! I should have mentioned that in the reply. Tyres should be matched to within 2" measured around the circumference, not the diameter.

 

To quote from the Yahoo Grops postings:

 

2" circumference, there is a vast difference.

 

A new NDCC Stalwart tyre will measure typically 12ft 8¾" in _circumference_

around the centre band.

 

The 2" of circumference represents just 0.622" in diameter and I very much

doubt you have a pair of vernier calipers big enough to measure this

accurately on a 48 diameter wheel with tyre.

 

Many Stalwarts are driven far further than this, as I have done, without

trouble, the British Army certainly did but always with well matched tyres

and meticulous servicing.

 

From a post by Richard Notton

[madrat]

Hi Guys,

Thanks for the response, I'm not bored of the Scammell but I am a bit bored of the 101 :cry: I love them to bits but I've seen the dark side! Always had plans to do a coiled 101 but my current one is too good to start messing around with.

 

Comments on loss of off-road ability noted, you will see from my scammell postings that I am rather partial to a bit of off-road activity! Long term I will need to get a low loader for transporting the Scammell but thats an expensive option!

 

I wasn't aware of how serious the wind up problems were, variations in tyre circumference make perfect sense and I could believe that they are more likely to cause breakages than a few twists and turn in the road.

 

Any idea how well they take to LPG? For off road use 'Red' LPG is around 40p/litre so a bit more sensible than petrol at 120p.

 

Thanks for the input, anyone going to have one at W&P?

[ArtistsRifles]

They take to LPG as well as any other B series. Problem you will have though is where to put the LPG tank. Anywhere in the load bed will restrict access to the major mechanicals etc... Between the false rear bulkhead and the tailgate will ruin the airflow for cooling.....

[Stormin]

Hi Guys,

Thanks for the response, I'm not bored of the Scammell but I am a bit bored of the 101 :cry: I love them to bits but I've seen the dark side! Always had plans to do a coiled 101 but my current one is too good to start messing around with.

 

 

No chance of trading my 101 then?

It's only in a few hundred pieces at the moment! On the plus side the engine and gearbox went back in this weekend.

Making a Stalwart 2 wheel drive sounds a bit expensive for recovery practice with the Scammell. Can't you find something cheaper to attach the winch cable to?

And if you make it 2 wheel drive how can you get it REALLY stuck?

[madrat]

I think I need to see one in the flesh to get my head around it all!

 

how can you get it REALLY stuck?

 

Getting things really stuck has never been a problem for me, there are some nasty bits out on the hill just ready to catch out an unwary Scammell or Stolly :shake:

 

Keep going with the 101 rebuild, the guy who bought my second 101 did an outstanding nut and bolt rebuild of it. You will end up with something very special.

[Mark]

Thanks for the input, anyone going to have one at W&P?

 

 

We will have one down in the quiet field, you are welcome to come and have a look over it.

[Poptopshed]

Access to the couplings for the shafts to bevel boxes is next to impossible and still very awkward with things like fuel tank removed. Well whats not on Stolly? :sweat: Its not practical to connect and disconect them with out modifications. I know it has been done using dog clutches on the shafts and can work well but as said above i would leave it as standard for the amount of miles its likely to do.

If your after a project our Mk1 is coming up for sale as we are running out of room and to many other things need work before starting on the stolly. :-(

[antarmike]

How does the end of the half/shaft/ tractor joint connect to the hub. Is it possible to bore the spline out of a spare set of caps and let the end of the half shaft turn slowly in the now plain bore of the hub?

 

I know someone who took this approach with a Unipower , a permanent 4x4 which doesn't have a centre diff...

[Grumpy]

How does the end of the half/shaft/ tractor joint connect to the hub. Is it possible to bore the spline out of a spare set of caps and let the end of the half shaft turn slowly in the now plain bore of the hub?

 

Mike

 

It’s just a simple spline sleeve that couples the two spline shafts together, held in place with a circlip each end. The main problem is they are right at the bottom of the hull and not accessible without removing the engine for the rear two and the fuel tank for the front two.

 

Duncan

 

Don’t worry too much about wind up on a Stalwart. Most of the problems people encounter with transmission failures is due to poor maintenance or daft driving technique, such as driving over cars or aggressive off-roading. The three wheels on each side are coupled together and then each side is coupled together via a non spin ratchet type differential. It is quite possible through aggressive driving for four or five wheels to leave the ground (especially driving over cars), the centre diff will lock and then all the torque will end up on one bevel box or tracta joint.

 

Keep it well maintained, the tyres matched and more importantly at the correct pressure throughout your journey and you will be very unlucky to get a failure, I’ve drove my Mk 2 thousands of miles on the road without transmission problems (hope I haven’t spoken too soon). Failures due to wind up are normally in the tracta drive and an easy repair and 99% of the time due to tyre size not matched or wrong inflation pressure. Bevel box failure is a nasty repair but again 99% of the time due to shock loads via aggressive driving.

 

If you really want to disconnect drive from a wheel station, the easiest and quickest way is to remove the sun gears from the respective wheel station. That’s the method used for suspended tow and only takes about ten minutes per station, however you must keep the sun gears matched with the station they came off as they are machined as a unit and are not interchangeable. There is a spacer you can put in the hub to replace the sun gears but to be honest its not really needed.

[antarmike]

I was thinking that on the outboard end of the half shaft, actually after the Constant velocity joint, there might be a drive plate with an internal spline to pick up the drive from the halfshaft, an series of holes on a P.C.D. to bolt to the outer end of the hub. (perhaps incorporating the Bollard cap.)