LRDG Pattern condensers

[Tony Smith]

Originally Posted by Tony Smith

As a curiosity, I see the tanks in both your photos have a filler using the cast brass caps from 2Gal POL Cans.

And as distinct from the both the Chev CMP Condensor and the Ford CMP Condensor, these tanks fitted to the LRDG Trucks have a filler cap to presumably pre-fill the condensor to say 1/3 capacity to condense steam from first operation to maximise conservation of coolant.

As the inlet hose seems to go into the filler cap (from a 2Gal POL Can), and there are apparent variations in the cans, I would suggest that these are not factory made, but made in Base Workshops as a theatre modification.

[Charlie Down]

Hanno, somehow missed that link. Not very impressive considering its my posting!
Tony, I agree, the variation in can sizes and design, as well as the quality of the finish, suggests a Base Workshop fabrication.

[David Herbert]

In the last photo in post #5 I think that the pipe most likely enters the can behind the cap, not through it. If it entered through it the cap would not unscrew, particularly as the pipe is at a bit of an angle which would be an unlikely feature if it were in the cap. I think that it is just luck that the photo was taken in a way that the pipe lines up with the cap.

David

[Lynn Eades]

Charlie, here are some thoughts. Some probably slightly off topic, but cooling system related:
Water pushed from the rad. into the overflow tank stays there until the engine cools and sucks said water back into the radiator. This is achieved because that pipe into the (overflow) tank goes almost to the bottom of the tank.
Most vehicles (Tony) used early in the war did not have pressurised cooling systems, just a plain filler cap. Fords, Chevs (ref. MB-C1) Dodge and most British trucks were like this. The pressure system was adopted during the war.
Overflow tanks work with both pressure and open systems.
Thermostats were alcohol filled (bellows type) these were usually wrecked if the engine boiled. (modern wax type are much better and fail when open)
Deserts are stinking hot in the day time but usually freeze at night necessitating the use of alcohol based antifreeze. (this lowers the boiling point of water)
Although Chevs had "steam pipes", if they were producing steam, they were already in trouble.
As Tony said, all the overflow tanks had to be vented. Any negative pressure in the system would collapse the radiator as it cooled.(assuming pressure had escaped)
The downward pointing breather pipe reduces loss from the system.
The cooling systems of the era contained a larger volume (for a given power output) of water, that had a "margin of safety" that modern vehicles dont have.
The top of most radiators stood high above the top of the engine, which was a hang over from the time of no water pump. They were called a "thermosyphon" system. The water circulates from the fact that the hot water moved to the top, constantly.
The thermostat is in the system to get the best out of your engine. The longest life and best power output comes from operating inside the designed heat range. So the thermostat is there to keep your engine hot. Cooling it is another departments responsibility.
Btw, you can see by the welding at the top of the can (2nd photo) that that can is local manufacture
A modern style radiator pressure cap not only holds pressure in the system, it also has a valve to let air (or coolant) back into the system as it cools. It's the little bit in the middle.
I hope this lot helps some people.
Check out the sole of the passengers boot.

[Charlie Down]

David, all the photos show the pipe passing through the cap into the condenser, presumably they could rotate in the tube in the cap to allow the cap to be screwed and unscrewed.

Lynn, thank you for the background on condensers. The anectdotes (which I am always open minded about) about water/steam venting from the condenser/radiator are interesting, and at odds with your comment about the damage that would do to the alcohol thermostat. I don't know if they 'upgraded' the thermostat in any way in the field or with the initial order for the trucks. but it looks like they upgraded as many features on the truck as possible to make it more robust and reliable when they placed the original order in 1941. The General Motors agent in Alexandria was consulted about the original order and most likely suggested various upgrades based on his experince of Chevrolet trucks in use in the Middle East and with the Egyptian army. I don't know if there was an option for the thermostat in the GM catalogue at this time, but the likelyhood of overheating was considerable on operations. They ordered the uprated radiator with shroud, and also had the 18" 6 bladed fan to help with cooling.

I'm also trying to work out the different sizes of these cans, and the correct details of all the mounts and how they were fitted to the 15332 truck. Photographs mostly show only a vertical metal strip bolted to the top of the bonnet/hood, and bolted below the can. Some show a horizontal strip in front of the can, presumably to prevent the heavy can swaying on the bracket.

The first photo shows S11 SIPOLILO of S2 Patrol. This truck has the base of a CMP seat bolted to the top of the stowage chest access hatch behind the front passenger, a more comfortable method of seating on the long patrols for the rear passenger, and not seen on any other truck in the LRDG. The worried looking bloke is an Italian POW. The boots do look like they are in an awful state.

Tony, the suede Desert boots, or 'Brothel Creepers' as they were also known as, were popular with mostly officers and NCO's. They were based on South African Bush boots and were produced after the War by Clarkes Shoes in the UK. You can still get them in the UK, and I frequently wear them in the summer. Still popular with current British soldiers as part of their off-duty 'uniform' of desert boots, jeans, unit T-shirt or hoody, usually adorned with appropriate in-appropriate message, topped off with a black North Face padded jacket.

[Tony Smith]

Clark's advert from the 70's:

[Charlie Down]

The future CO of the LRDG, Jake Easonsmith, wearing desert boots. Jake's family live a couple of miles away from me near Bristol, UK, and played at our local Rugby Club pre-war.