[nastypurplenova]

(1972 Chevy Nova)

I've worked out most of the kinks in my car, now im working on the heater. It only blows cold air (not a/c, just air). I thought it would be the heater core because after the car heated up to about 180°F, the hose from the water pump to the core was cold, except about 2 inches from the water pump. Is it possible the water pump is clogged or should I try messing with things inside the car (switches/ducts/cables)?
Also, after searching google images for how the heating/cooling system hoses are supposed to be routed, i noticed mine is a lot different, not sure if it made a difference though. The hoses go from my water pump to the heater core, then the heater core to the radiator, but most cars have it going back to the engine block... of course I think the spot on the block is taken by my temp gauge.

[matts37chev]

make sure the valve that controls the hot/cold opens and closes letting water flow through the heater core.
check the operation inside at the controller and make sure the same is happening under the hood or dash (where the valve is).

[DanTwoLakes]

Let's move this to General Rodding Tech.

Dan

[nastypurplenova]

Looking under the dash I can see the temperature wire move as I adjust it and I can feel a difference in how hard the air blows, but no difference in the air temp. I did this while the engine was running for about 15 min.
I also felt the hoses again and they were cold except right by the water pump.

[LATECH]

Your problem is that the waterpump is where the cold coolant from the rad enters the engine. You need to move the hose from the back of the pump to the spot where the coolant sensor is. Put the sensor in the side of the drivers side cylinder head where it belongs, you will have heat then.
With the hose at the waterpump you are c circulating the water from the radiator to the heater core. The coolant has no heat in it there. You need to tap it from the area next to the thermostat.
If you were to loop the hoses from the water pump to the fitting on the intake and eliminate the radiator fitting, your heater would work sooner as the engine would warm up faster as the coolant would not circulate through the radiator untill the thermostat was opening
The heater would also work better as a result too

[nastypurplenova]

wow, so stupid how that was overlooked. It didn't really occur to me until you explained it, latech.. obviously you want hot fluid running into the core but for some reason in my head it made sense to get the fluid from the water pump. Anyways, thanks man

[LATECH]

Thats OK, the return side from the heater is in the water pump as is the return from the radiator (lower hose)any place else is good for hot water!