|Fresh Water Circulation Diagram
All Models Except M-15
Normal Range 165 to 195° F
1. Coolant (fresh water with antifreeze) is introduced into the system from the coolant section of exhaust manifold by removing pressure cap and filling manifold tank within one inch of lower rim of fill port.
2. Fresh water engine driven circulating pump moves coolant from heat exchanger through engine block circulating pump and thermostat back through exhaust manifold into heat exchanger to be cooled.
The manifold serves as the engine expansion tank to allow for expansion of coolant as it is heated. You also fill the system at this point. In some cases when hot water heaters are installed an expansion or surge tank may be required to prevent air from entering the system.
Should your engine overheat, first check coolant level to make sure it is not low which would cause air locks to develop. If air does enter the system, it may require a couple of fillings to remove the air pocket. A momentary increase of engine RPM to approximately 2800 to 3000 RPM may aid in moving the air from the system. In some cases it may require doing this 2 or 3 times. Do this just as you notice the temperature starting to rise above normal.