The Classic Machinery Network

Some of my Fowler Challengers ...................The last photo shows from left a Challenger 3 with a Leyland 600 motor and a Fluid Drive, Challenger Mk III with a Leyland 600 and a Challenger 1 with a GM 3-71 out of an Allis Chalmers HD7 fitted to it. The first photo is a Challenger 4 with a Meadows 6DJ970 motor. This motor had a seven bearing shaft, four valve head, direct injection with toroidal cavities and automatic timing advance all in the early 1950s ........ not unique but fairly adevanced at the time.The dozer blades are all Aussie built ...... the first two by Malcolm Moore Industries in Melbourne, the Challenger 1 blade was built in Toowoomba, Qld by Walsh Engineering.

Gudday Don surprisingly there must have been a few of challanger crawlers exported out here as they seem to come up for sale every now and then I have some photos some where of them been used in WA on grain farms with multi hitched plows and combines . I wonder how many they sold out here ?
Every time I see one for sale I am always to late but I will keep on looking
thanks for sharing

Paul

Quite a few Challenger 1s and 3s Paul ..... not many 4s though, I know of only 3 (confirmed) in Oz but there will no doubt be more. There were of course hundreds of Fowler VFs and then the later Track Marshall 50 and 55s sold well with a total of around 700 here ..... many still working. The Challenger 3 was a fairly reasonable machine but the Challenger 1 had big issues with the motor hence quite a few had transplants.

There was some challenger 33s belonging to Monks on the Berks section of the M4. Flash Harry, Tom Mcgill,and two more names I can't remember drove them.

Fred on his old steed in 2012
Martyn

Hi,
When I was out in Oz back in January enjoying Dons', (Marshall MP6s), hospitality I was interested to see what Moore Road Machinery had done to mod. the Challenger 3 for the Austrailian Market.
It made no sense to me then and I still don't understand "WHY WHY WHY " they went to so much trouble.
To start the story with a bit of background info. the Challenger "3" or Mk."3" as it was then called was designed to use a Maeshall ED8 engine which ran at 825 rpm.
The engine proved a disaster and they went on to use Meadows and Leyland units which ran at 1,550 rpm. This created a problem and rather than redesign the gearbox and final drives they fitted a reduction gearbox ahead of the main gearbox. ( F in pic. below).

This box was bolted to the flywheel / clutch housing and reduced the shaft speed at the main gearbox input to 825 rpm. in line with the original engine speed.
Don casualy mentioned that his "3" was fitted with plannetary final drives. "May have been fitted retrospectively," he said.
These finals had been designed for use in the Challenger"4" and the later "33" they provided double the reduction compared to the original Challenger "3" bull gear & pinion finals.
They elimminated the need for the reduction box described above.
What Moores had done was to fit a Vulcan-Sinclair fluid flywheel between the engine and the main clutch. ( See Dons Pic below).

This left no room for the reduction box and it was a while before it dawned on me. The planettary finals had been used by Moores in order to obtain the reduction in ground speed in the absence of the reduction box.
The question is still "WHY " I don't know the driving technique, but what's the point of the fluid flywheel Its hardly likely you would want to use the clutch, gear levers and hand throttle every time you change direction. It would be painfully slow.
Fluid flywheels were normaly used with semi automatic transmissions eliminating the need for a clutch.
in this case it was still necessary to use the clutch to change gear and though the fluid flywheel takes up the drive as the revs. increase it doesn't increase the torque and gear down under load like a torque converter.

Thanks Fred sounds to me like a question of famous crap British engineering.

Jeremy

Am I wrong, in regard to some dozers like older Allis Chalmers and Cats which had a fuel filled torque converter as well as a main clutch, they didn't "gear down" either under load but instead spun slower for the given engine output (under load) and thus this increased the torque delivered?

Trev your are not wrong you are one hundred percent correct that way the dozer is heaps more efficent as there is no stopping to change gear all the time

Paul

I think it still sort of depends on the country a little, but yep, generally any of the older dozers I have driven (not that I've done that much work dozing) with torque converters, had half thereabouts, of forward and reverse gears, compared to a straight box for the same model.