Welcome to, The home of the PCCA => General Help- Ask the Experts... => Topic started by: pinto bismol on October 27, 2014, 05:53:13 PM

Title: heater issues
Post by: pinto bismol on October 27, 2014, 05:53:13 PM
well, for the first time since I got her it is cold enough to turn on the heat.
It's blowing cool air. grrrr! changed out the heater control valve and checked the coolant level.
Thermostat next? Heater core maybe? what's my next check before I just buy all new stuff?
Title: Re: heater issues
Post by: 76hotrodpinto on October 27, 2014, 10:41:06 PM
If you drain some coolant you can disconnect both heater hoses, water pump and manifold. Then try to blow thru it, do not use a compressor, just man up and blow it. If it's passing air it should be ok. There are also two gaskets that are on either end of the intake manifold, I've seen people use gaskets that block the coolant at one or both of these passages. I don't know why, just undone a few. Hope that helps.
Title: Re: heater issues
Post by: sedandelivery on October 28, 2014, 06:56:01 AM
When your engine is nice and warm, feel your heater hoses to see if both are warm, If not, the core could be blocked. If the radiator doesn't really get warm, it could be the thermostat.  If all that is good, see if the cables going to the blend door are hooked up correctly, there are plastic clips on there that do break.
Title: Re: heater issues
Post by: Jerry merrill on October 28, 2014, 11:02:20 PM
I just got my heater working, in my case I had one heater hose hooked up to the water pump and one to the fitting on the thermostat housing which only flows when the thermostat is open which during the winter is almost never with the 190 deg. thermostat in it. Finally put a fitting on the intake manifold and switched the one from thermostat housing, now works great.
Title: Re: heater issues
Post by: oldkayaker on October 29, 2014, 03:00:25 AM
The heater hose connection opening in the thermostat housing is on the engine side of the thermostat diaphragm so the heater hose connection should be flowing at all times when the engine is running .  If it is not flowing, maybe it is corroded shut, or thermostat is installed backwards, or?  From what I can determine, the intake/carb connection is to keep them from freezing up and keep the fuel atomized.  If it is cold where you are at already, this would be a good thing.
Title: Re: heater issues
Post by: amc49 on October 29, 2014, 10:01:59 AM
If stat not closing all the way to make good heat  it will reflect at the temp gauge if working right, the needle will be somewhat lower than normal.

Make sure if a/c is equipped with a bypass door that the door is closing or no heat at all since the air does not go through heater core, rather, it shortcuts at the bypass door. My Focus does not heat at all because a stupid plastic shaft stripped on the airbox and no heat. I have to climb under dash and flip a door by hand to make instant heat. Done in seconds but not pretty when you weight 250 lbs. You have to yank the dash to fix that shaft, not ready to go there yet (if ever).