Aussie Thornycroft

[mammoth]

I looked at this one several years ago and what with various personal hiatus never got round to posting it here. What model is it with the strange rear cross members? and is engine (L4 408) correct?

Owner has changed direction and offered it to me so before committing I would like to know more about it.

 

[Tomo.T]

I think that may be a K type Thornycroft,  fore runner of the J, with an L4 engine, which was upgraded to the M4 for the J & X series.

[Tomo.T]

I looked it up and the good book says L4 (30 hp) engines were fitted to H, early J and K models. The M4 was a longer stroke ( 6 inch instead of 5 ) which boosted output to a massive 40 bhp !

[mammoth]

I think we have been reading the Townsin book in tandem, and that is the limit of references I can find on those models.  The Aussie one has a worm drive diff whereas Townsin indicates that the  K subsidy models were double reduction bevel, but what about the H and J (pre 1914) ?

Can we rule out the earlier 40L4 or 50L4 models on the basis that they were chain drive?

[Tomo.T]

I'm already in over my head tbh. I have seen pics of one other chassis with raised cross members in NZ, which is also unidentified. It's certainly pre war and quite rare I would think.

Edited April 2, 2021 by Tomo.T
more info,

[Tomo.T]

On further reflection, The worm drive diff looks more like an early J type.

[nz2]

Delighted to see another early Thornycroft of the same pattern as one I have. Small diameter front wheels, track rod to the front, spring hangers to the front, raised chassis cross members  over the dif, and a five piece dif housing. It has been twenty plus years of waiting!

[nz2]

pm sent

[mammoth]

I wasn't able to find a chassis number at the time of the last visit. (about 4 hours away) The engine in the photos is sitting on timber, not on engine mounts so I will need details of how it is mounted. Also missing is the induction manifold and water pump. I doubt that this is the original radiator;- what should it look like?

[nz2]

Engine dated leaving the factory 28/1/1914 in a J model.

[mammoth]

I now have the relic home (pics to follow later)., No chassis Number to be found anywhere but it does seem that the engine belongs with the chassis. With help from Doug and the on-line chassis lists the chassis number would be 1379 and described at "L4 chassis" . It was despatched through the international agent Tozer, Kemsley & Fisher to be sold by W.F.Turk & Co in Brisbane who at the time claimed to be sole Thornycroft agents. The vendor can't even remember who he bought it from so provenance is scant, although he thought that it last worked as a timber jinker, perhaps somewhere in the Darling Downs region.

Now, while this chassis matches the description of "pre-war J model'  maybe it is time to present the 'quacks like a duck' scenario. The J model variants that everyone is familiar with have;

a different engine

a different gearbox,

a different differential

different size front wheels and track rod position, & etc

Accordingly,. do I have a consensus for a historical revision and call this an  'L4 Chassis' rather than a 'J', or perhaps 'L4J'.

In the absence of any technical material in my possession I have taken some dimensions and invite comparisons with the later J.

Wheelbase; 13'  wheels, F; 660x120 R 800x240; Chassis width F, 361/4", R, 413/4" Rails 61/2" x 2"

Springs; F, 21/2"x 8 leaves; R 3"x 12 leaves

 

 

[Richard Farrant]

Hi Mammoth,

Have you tried contacting the Hampshire County museum in England that hold the Thornycroft company's records? Here is a link;

https://collections.hampshireculture.org.uk/transport-vehicles

I did this for several Dennis vehicles of similar age through the Surrey museum and got copies of the build sheets and these were for lorries exported to Australia, they were very detailed.

regards, Richard

[nz2]

10 hours ago, mammoth said:

 

"Accordingly,. do I have a consensus for a historical revision and call this an  'L4 Chassis' rather than a 'J', or perhaps 'L4J'."

 

   From the Thornycroft Progressive Number Register book the chassis is described as a CH J .

What the CH refers to I have not been able to work out as it is only used to describe a small batch of J and K models. There after the CH is not used.

 The L4 engine had been well used in lighter chassis types, all being chain drive at that point in time.  They were described  by engine type and chassis weight  capacity in cwt . Hence L4 50 or L4 40.

The lighter model was the M2 at 30, 40 or 50 cwt. That two cylinder engine  became the basis of the M4 engine of WW1 fame by adding a second M2 pair of cylinders to a new crankcase housing, new crankshaft and other necessary bits. 

  The great thing is the chassis and parts Steve has located  is more complete than mine, for I don't have a gear box and have long queried as to the gearbox type. The L4 is rated at 30hp and the chain drive transmission is a different format to shaft drive needs. The M4 engine is at 40 hp  so was there a new gearbox for the M4  or upgraded from the 30 hp  shaft drive unit. 

 I have an L4 engine  however that is recorded as being from a L4 50 originally, the chassis and engine therefore from different vehicles. 

 Doug 

 

 

 

 

 

[mammoth]

The radiator top and bottom tanks as well as the sides are all cast in brass - someone must have loved it to make such an investment. As the front is plain as cast I would like a mould taken from a similar age radiator to make a 'badge' for mine.

There is sufficient here to 'restore' back to factory condition, however there are a number of 'bush mechanic' features that might be conserved, for example, the chassis flitching, and the oversize tyre bands fitted by timber spacers.

 

[mammoth]

The gearbox, quite different to the later type. The top cover is a brass pressing. Timber engine mounts, surely this can't be right? Gear quadrant is part dismantled so is out of position.

[mammoth]

The diff

Precautionary flitching at midships promoted a large crack at the rear and so a repair was required

[mammoth]

[mammoth]

The left stub axle has a 'J' stamped on it. Kingpin brass covers missing.

[nz2]

I can use the word same so many times when comparing those photos, except for the circular gearbox which I don't have.

 Doug

[mammoth]

While the identity of this chassis is now certain there is much head scratching as to the specification. The only stamped numbers found so far are a 'J' on the left swivel hub and 'J04" (what could this mean?) on the right one.  

 

Has anyone seen the unique gearbox with circular aluminium case like this one any where before?

 

Doug has previously scoured the archives  as far as  correspondence allows, however as Ben has noted on his BT thread it appears a physical search can turn up items that have gone unrecorded. 

Any leads to literature and L4 engine parts would be most welcome.

[mammoth]

I was mistaken with the gearbox case and fooled by the silver paint;- it is steel, with a lathe turned finish.

More details around the petrol tank. The right side member must be original as it is shaped to take the hand brake mechanism. Nice filler and the petcock can be restored. The gap under the fixing straps must have held something, not the seat as the tank is too lightly fabricated to take the weight.

[Tomo.T]

A lot of uncharted territory here and considerable differences from the 'Subsidy' model, which was in full production not long after this was supposedly built ? I wonder if it was an experimental model, (J 04) later sold off to the colonies ?

Engine mountings are straight forward enough on later J types, all you need is some heavy 3 inch angle iron as shown here.

The other side is just a 1" whit diameter pivot, which supports a bushed rocking bar between the two engine mountings, thus providing a bit of 'give' when the chassis flexed.

If you have a 1 inch hole at this point in the chassis, that will confirm the engine mounting was the same. Otherwise it might have just had four angle plates, which have been replaced by lengths of wood for greater flexibility ?

You are no doubt aware that your chassis has been cut short, presumably for 'timber jinking' 

Good luck with the restoration.

[nz2]

Tomo T comments regards these being a prototype is always a fair point. The build register shows the use of the M4 engine being available from July 1913, however it appears the L4 engine continued to be more popular by demand. Well at least more were supplied in lorries passing out of the factory. 

 The point of sending them to the Colonies  also raises issues, for many are listed as being supplied to the home market. Tozer, Kemsley and Fisher were exporting agents also sending products from many other different manufactures all about the world. Although their name appears regularly on the dispatch column there is no indication as to where these vehicles went to.

 To make things a little easier for me in New Zealand, a local firm of A. Hatrick & Co. began importing Thornycrofts, placing their first order on 30-8-1912.  To confuse the issue Hattrick's also had an office in Sydney, and there are still Thornycroft's in Australia with a Hatrick agency name plate. No records are known to have survived from the Hatrick companies covering the imported chassis numbers. From the Thornycroft production records the Hatrick name appears fifty five times to April 1915, the last five being ordered after the commencement of hostilities. Eleven different models are recorded as been  delivered.

These early J models did have their problems in France during the early months of The Great War with the major repair depots making changes to the vehicle parts. Apparently a replacement rear axle casing  was designed and cast in France by the depot, to replace the five piece diff housing as used on these early J's. This then became the standard when the J model was repowered to the M4 engine  in August 1915.

 From Steve's photos we can see the gearbox was another item that received a dramatic change in form, along with the position of the fuel tank. Other changes to the Subsidy wagon included the steering track rod being moved to behind the axle, the front wheels became larger and the front spring hangers were moved from the front to the rear end of the springs. 

Steve in providing these photos and passing on more data by email has greatly assisted in allowing the similar J here to progress further towards restoration, for now there is another one to compare with.  

 Doug 

[BenHawkins]

I don't remember seeing anything on early J types/L4 engines during my visits to the archives but I will go through what I have and see if there is anything relevant (I tend to photograph everything I can, if permitted).

Visiting archives in the UK has been nearly impossible for a year due to the Covid situation; hopefully access will improve later in 2021. I have more Thornycroft stuff to go through so I might turn something up. For one of my other projects I put in a request to the Toyota museum in Japan earlier this week; they responded within 24 hours having taken 20 photos of a vehicle for me - Japanese efficiency.

[mammoth]

 

On Doug's recommendation I have just obtained a copy of "Benzine Lancers' by Rod Dux which is about the mechanization of the Australian Imperial Force. When war was declared the force had zero vehicles to it's name and with the ever loyal  colony eager to come to the empire's aid a contingent was put together. All up 130 odd new and second hand trucks were purchased of which only 6 were Thornycroft and it can be reasonably be presumed that these were the early J.

Interestingly the very first shot fired in the war was on a German ship which blundered into Melbourne's port - so that was 6 new Benz's to swell the list!

The concept that this model was  a prototype or experimental is not so silly. While Thornycroft had used riveted folded steel chassis in cars and light trucks with success this was a step up from 2 1/2 tons to 3 1/2 tons, and their first attempt at worm drive. Putting the front axle shackles at the front wasn't a success as the rear spring hanger was not up to the job and the arrangement did not lend itself to the normal arrangement of fitting tow hooks. The civilian J did not have tow hooks however a photo in the Dux book of the J's sent from Australia shows straight tow hooks bolted to the chassis rail  and it could well be that the 'modified hooks' mentioned in Tommo's thread could in fact be these. The AIF collection of trucks was a real mish mash of makes and when they eventually (after service in the middle east) reached Britain they were swapped over for a standard WD fleet.

The Australian mechanization was intended to be fully in lock-step with the British and since I don't recall the entire specifications for trucks being put on this forum here is the version as it was used by Australia.  However, bear in mind that the War Office subsidy specs kept changing.

War Office SPEC.pdf

Edited March 25, 2021 by mammoth