help with the heater

hey guys i'm having trouble with my heater on my 1981 Fairmont wagon. the blower motor blows hard but its just not blowing hot air it has a newer heater core and the heater lines are on right. i went yesterday and got a used heater and a/c controls still no hot air i'm stumped and it seems the car isn't getting warm enough the temp gauge stays around 160 - 170 so i don't know. i wonder if the heater core is stopped up? it has a 200 straight six with auto and a/c. oh i would like to ad i installed a new radiator a couple years ago and used a v-8 one i wonder if its to big for the 6 cylinder? and its cooling it to much?

 

Peg legs
Check the Heater control valve / water valve.
It sounds like it's not opening to let the hot water in to the heater core.

Let us know what you find.
Good luck, Rick

 

i checked that rick and this model fairmont doesn't have one.

 

There's 2 possibilities:

There's an air lock into the heater core, which only needs to be bled, while the engine is running. You can buy a valve kit for that or use a bucket with the return hose draining into it (the hose that returns to the water pump.

OR, your intake vacuum motor is stuck open or not working at all.

A longshot 3rd possibility:
The easiest starting point is the resistor on the heater box, below the dash though. They usually don't fail, but... Pull off the connector and test the Temperature switch with a lightbulb current tester (2 prongs on an old bulb socket.

 

Odd
Are the heater hoses hot when the car is all warmed up?

 

norman the vacuum motor is working and the resistor so i'll check and see if it has an air pocket in the heater core. i just wonder if its almost stopped up?

rick: yes the heater hoses are hot when its warmed up.

i still wonder if having a 3 core radiator is my problem i just let it warm up and drove it and it only gets 160 - 170 even in traffic.

 

You have a new neater core so I doubt that it's stopped up.
Can we assume this car has no air conditioning?
I'm with the air bubble in the system, needs to be bled out.
I usually start the car cold, with the cap off the rad. When the thermostat warms up it'll open and you'll see a trickle of coolant start when you look in the rad. The level should go down at that point. Do NOT rev the car!
When the level goes down you can add coolant to top off. Do you have the hoses hooked up correctly?
Yah that rad could be overkill for the little six.

 

It's not your radiator,I put a 3 core our Mustang 200 six cyl
The heater works fine, If the heater hoses are hot that tells me two
things. 1 the water is not getting in to the heater core or 2 the door is not opening inside the heater box to let the air flow through.
check the vacuum lines for leaks.
Rick.
One other thing Make sure the core is not plugged,sometimes they can get full of rust "Why did you change the radiator"?
Rick

 

it has air conditioning and i checked dad's mercury monarch's heater hoses and they are ran the same as the fairmont. i'll try to bleed the system later today.

 

........ya....got here late....iz all been said

 

Thermostat. Already replaced 2 this year. One in the Cruiser and the other in the wife's Blazer.

 

The thermostat on the this engine doesn't control flow to the heater core.
The flow goes straight from the water pump so it should heat up right with the engine.
An air pocket due to not enough coolant due to a having a giant radiator might cause the pump to cavitate.

 

You're right to a point..........there might be an air pocket, but doubtful. Just leave the radiator cap off until the thermostat opens up and if that is the problem, it should fix itself. Now, the thermostat has a LOT to do with whether or not you get proper heat. The 'stat closes when cold. It opens when a preset temerature is reached, usually 160, 180 or 195 degrees. The 'stat stays closed and water is circulated via the bypass hose until warmed up. Most cars have a bypass system. I don't know of many or any that do not. Anyhow, if the thermostat is open, or the spring is weak and it opens too soon, you will NOT get much heat. A sure indicator of this is if the temperature guage shows less than the value of the 'stat that is installed. Just today it was 26 degrees and my Cruiser was frosted over. I started it, but it never warmed much. The heat was warm, not hot like it used to be. The guage only showed about 150 degrees. I knew immediately that the 'stat was bad. I bought a new one and installed it this PM and the heater will run you out, now. An open 'stat will make the engine run cold and a stuck closed one will make it overheat.

 

Dodgeguy, one more thing. My 302 V8 had a nice 6 blade fan (not thermal clutch - Mexico didn't offer them as options - too hot all the time.) I was so happy that it fit right onto the I6 waterpump, because the wimpy 5-blade fan didn't look like it could keep the engine cool enough. The previous owner mentioned that it ran hot. I can't get mine to the O in NORMAL on the Mustang gauge. Don't get much heat inside either.

 

I have never cared for clutch fans. I prefer flex fans. If your engine is not heating up to normal, I would suggest replacing the thermostat. As mentioned before, it regulates engine temp and must be working to get decent heat. You can check some things, are BOTH heater hoses getting HOT, not just warm? Did this problem just start or something that has been going on for some time? There is (or should be) a heater control valve on there somewhere. Might be under the dash. See where the cable goes that changes the temp from cool to warm. Might be vacuum operated, but I guarantee there is a water control valve on there somewhere. If there were not, you wouldn't get much AC in the Summer. Make sure it is opening and closing. Take both heater hoses loose at the engine/water pump. Take a garden hose and squirt water in one hose (preferably the one coming out of the core) and see what comes out of the other hose. Then reconnect, top off the radiator, run engine and see if there is any better heat. I still believe the 'stat is bad, assumeing the gauge is accurate. You can pretty much tell if the engine is warming like it should by driving the car and checking how hot the radiator feels to the touch, as well as the hoses.