question WW2 Military Bulldozer

[mtskull]

A query from a certain Mike Harding (who I am sure some of you have heard of):

 

"Serious question - any motoring experts out there who know whether WW2 Army Bulldozers 1945 (ish) would have used diesel or petrol? I know it seems daft but I need to know for something I'm writing.

 

[peter75]

Most were diesel.

Cat and International had petrol engines as alternative to diesel engines for some modles e.g. International T9 petrol and TD9 diesel.

Peter.

[ploughman]

Didn't the D8s have a small petrol donkey engine used to turn the main engine over on starting?

[Richard Farrant]

Didn't the D8s have a small petrol donkey engine used to turn the main engine over on starting?

 

The D2, D4 and D7 also had petrol donkey engines

[peter75]

The TD International's started on petrol and switched to diesel when warm.

They have a mag and plugs on one side and pump and injectors the other side.

There was a leaver which switched between the mag and the injection pump and shut off part of the head in the combustion chamber.

Peter.

[hummermark]

Not a bulldozer but allis-chalmers he-10w tracked heavy tractor m1 had a Detroit diesel 2 stroke 4-71 1940-1943 used by the us military

[Richard Farrant]

I think the Clark airborne dozer was a petrol engine

[Degsy]

The Vickers Alecto bulldozer prototyped just before the end of the war was fitted with a Meadows petrol engine.

[david1212]

The TD International's started on petrol and switched to diesel when warm.

They have a mag and plugs on one side and pump and injectors the other side.

There was a leaver which switched between the mag and the injection pump and shut off part of the head in the combustion chamber.

Peter.

 

Interesting to find that this was possible as I thought petrol & diesel engines had significantly different compression ratios, something to read more about when I have time.

[g0ozs]

I think mixed fuel engines were quite popular at one time - when I was very young in the 1960s my father had a Fordson 1/2 track tractor with a petrol-paraffin engine that used magneto ignition and switched to paraffin/kerosene once it was warm - I seem to remember huge clouds of white smoke and a very vicious starting handle with a habit of trying to whack my dad !

 

I suppose the idea is that Petrol is easy to cold start but kerosene or diesel are (were?) cheap

 

Iain

[Degsy]

At one time almost all tractors ran on tractor vaporising oil (TVO) and were started on petrol switching over as they warmed up, many still survive in preservation, the majority of the grey Fergies are a typical example.

[Adrian Barrell]

Interesting to find that this was possible as I thought petrol & diesel engines had significantly different compression ratios, something to read more about when I have time.

 

They do and to allow the changeover, International incorporated an extra part to the combustion chamber which contained the spark plug. When you pull the lever to switch to diesel, a valve shuts off that extra part increasing the compression ratio. It also turns on the diesel and switches off the magneto. Quite ingenious!

[david1212]

They do and to allow the changeover, International incorporated an extra part to the combustion chamber which contained the spark plug. When you pull the lever to switch to diesel, a valve shuts off that extra part increasing the compression ratio. It also turns on the diesel and switches off the magneto. Quite ingenious!

 

Thanks for the detail, I did wonder if somehow the capacity / compression ratio was changed rather than simply turning off the spark ignition system.

 

I knew about tractors in particular being started on petrol then switched to paraffin as cheaper but that the running principle was the same.