New radiator,new water pump, timing belt, new thermostat, water barely trickles out from engine block hose to heater case.Radiator water level good, water temperature normal. Will get cold here soon in ND. Radiator shop guys are scratching their heads on this one. HELP!

 

Disconnect both heater hoses from the engine, turn dial to full hot, and flush plain water both ways through the heater core from a garden hose. If the water doesn't flow freely, find out why. It could be the valve or the core itself can be stopped up, especially if "stop leak" agents have been used in the car.

Then re-connect the hoses and refill the system. You have to run the engine for several minutes with the radiator cap off to purge the air out of the system. Keep adding coolant to the radiator as it goes down. During this process the car must be level or facing uphill so that the radiator is the highest part. The heater dial needs to be on full hot. The heater fan does not need to be running.

Check that the heater valve opens fully with dial on full hot. The air door inside the dash also needs to move so that air quits bypassing the heater core. This is all controlled by a mechanism on the bottom of the heater box in the center of the car under the dash.

 

Thanks a lot for the tip! I will definitely give it a try and let you know the result.

 

We'll, the shop had tried all those suggestions but still no heat. I may have to take it to a mechanic since there is no water flow out of the engine block to the heater box, any other ideas? ... Thanks !

 

You'd do the same thing with the fittings on the engine that connect to the heater hoses-- flush with a hose to make sure they are not obstructed. Obstruction there is unlikely unless the system is REALLY dirty or corroded.

And if you didn't carefully refill the system to get all the air out, the heater will not work because there will be a bubble of air in the top of the engine that prevents any coolant from flowing to the heater.

Clearly you need to go to a different shop, one that actually knows what they are doing.

 

Thanks, I didn't realize an air bubble could so easily be left in the system, & would cause the coolant to not flow to the heater box, hopefully this will get resolved this week at a new shop, a guy that was recommended to me that is a honda specialist,...thanks!...Will repost later.