The factory block heater quit on my truck, so I installed a tank style recirculating coolant heater. I installed it inline with one of the heater hoses, but it's not working at all. Has anyone installed one of these? Where did you hook up to? I would like to hookup to the head near the back but I can't find a good place any suggestions? I think I shouldn't have any problems drawing coolant near the lower rad hose, but I'm not sure where to hook up the return line.

Thanks for any help

 

I would hook up the return line as far back on the head as you can. A fitting behind the fitting for the heater core hose would work. I have my Espar, a diesel fueled coolant heater, plumber in series with my heater core and it works really well. It's odd that yours isn't working. Does it not pump, make heat, or a combination?

 

My return runs through the heater core and then enters the head right behind the thermostat, I think the thermostat is opening and causing all the warm water to flow through the rad. It will heat up the hose to the head but then a couple hours later the hose is cold again.

Is there a fitting I can use near the rear of the head? I don't remember seeing one back there, but I guess I'll have to get under the hood and search, not fun since it's -30c (-22f) right now