[CWPASADENA]

How do you have your heater plumbed?

The best way is to take water from the upper water outlet (below the thermostat) and return it to the water inlet on the side of the engine. this allows the water returned from the heater to re-circulate back thru the engine. Some plumb the heater so the return water is returned to the upper hose above the thermostat. This water then is cooled more by the radiator before it reaches the engine to be re-heated.

Also, there should be a bleed hole in the thermostat to bleed the air that it may trap. sometimes these bleed holes have been enlarged. I think a bleed hole should be no more than 1/8 inch and may be even smaller like 1/16 inch. All the water that goes thru the bleed hole has to also go thru the radiator and then be returned to the engine. Just be sure no water is by-passing the thermostat except for what goes thru the bleed hole.

Chris W.