I know its not military but our group has a problem.
We would welcome any suggestion as to a cause and even better a cure.
The Dorman Diesel in our 12t Plasser Rail Crane has been overheating badly recently.
As part of the investigation our fitter has already examined and checked the water pump for correct operation and found no fault.
He has also done a compression test on all cylinders and found nothing to be concerned about.
The engine oil is staying clean and not becoming emulsified, likewise there does not appear to be oil appearing in the coolant.
If water is being evaporated in the exhaust this is not obvious, but may not be so easy to see.
Without boiling the amount of water loss is high even for a short period of running and only appears to be venting from the expansion bottle once the coolant boils.
A new radiator cap has also been fitted, in case this was the problem.
What is really baffling is where all the water goes. There are no obvious leaks when the machine is stood, and even after a short period of running, say 30 mins, then needs a top up of 2-3 gallons.
I am not sure what the total capacity of the cooling system is, I dont think either the Plasser or Dorman manuals gives us this figure, but a loss of this amount of fluid must be a good percentage.