Engine Pre Heating Connections?

[Kevin Means]

Hi all. We'd like to install a diesel-fired hydronic engine preheater in our 1998 M1083. Ours has a stock 3116 Cat. We're looking at the various heaters, but I was wondering, where exactly do you connect the input and output hoses in the engine compartment? When preheating the engine, how does the coolant circulate through the engine block when the engine's thermostat is closed? Thanks

Kevin

 

[Ronmar]

You use one port on the thermostat block(pre-thermostat) same place where the cabin heater is fed from. You could T off the cabin heater supply port. There is a port with an Allen head plug on the side of the engine block all the way back by the transmission/bell housing on the passenger side.

since both these ports are on the pressurized side of the water pump and thermostat, i doubt you would experience any short circuit flow when the engine is running, feeding hot supply at one port and return at the other end of the engine should distribute heat thru the entire length of the engine block and head…

 

[Keith Knight]

I was also thinking of doing this project. I currently run a diesel hydronic heater for the habitat heating and water heating. I don’t like the idea of using that one for the engine I’ve heard of bad stuff doing that. So I was thinking about adding a second one for the engine because my 120 vac block heater pulls so many amps and even after an hour it’s still not warm enough to crank easily in temperatures below 25.
What brands of heater are you considering?
Mine is an Eberspacher and works great but they are pricey for the few times I need it for the engine.