Hi all. Now that ive started driving my 64 f250 everyday again its time to start fixing little things here and there and just generally fixing it up. I live in Wyoming and right now im living in Laramie which is over 7000 feet, in other words its colder than H#$$ 9-10 months out of year. I can remember when i first got my 64 it seemed the heater would cook you out but that was when i still using it for ranch work so i was typically wearing full carhartts anyway. Now it seems like the heater works but just enough to take the edge off in the cab not really warm it up. So im thinking its time to get this thing working. Im just wondering how good your guy's heaters work and where to start looking at mine. What about the aftermarket heaters available are they a significant improvement over stock and do they mount easily.

 

Does it have any kind of insulation? Is the heater blowing hot?

 

When is the last time you flushed out the cooling system, and heater core, large amounts of Debris in the coolant ie; rust and what else can plug up the passage ways and hoses for the heater, a good flushing with a garden hose and maybe some Radiator cleaner can make a big difference, both in the heater, and also in how cool your engine runs in the summer heat. Just a thought!

 

Well the heater seems to only blow warm not really hot, im thinking either the core needs flushed like mentioned. Or i need to change thermostats and or fans to make it run a little warmer since it seems to run on the cool half of the gauge, or maybe something is going on with the water pump and its not pumping the water through the core good enough.

 

My heater blows hot always has. I have a new radiator, new thermostat, completely flushed system. Even before doing that my heater blew hot air.
As mentioned already flush your system replace what you can.

 

if it is a water pump issue you will certainly have a high temp reading on your engine temp..... if the engine is running rather cool check to see if your thermostat is stuck open.... but start with a flush and then go from there..... eliminate the easy and obvious first....

 

Sure sounds like the T-sat is stuck wide open if its not getting up to operating temp as these trucks use a 180 degree T-sat.

 

Well i replaced the thermostat a year or two after i got it. Maybe they gave me a colder one. Also my fan is pretty radical and fixed so its always pushing a lot of air.

 

Have you ever taken off the cover of your heater and cleaned it out? Another place I try to clean out every year is inside the vents in the kick panel and make sure dirt isn't plugging up the drain hole, so water that drains down from the cowl vent doesn't start rust in there. I have always found alot of dirt, leaves,straw/hay and pine needes around my heater cores in the past. Does your truck have the fresh air heater with the 2 pulls under the dash? If you do is the heat cable actually opening the valve mounted on the right inner fender? If it doesn't and the heater hose comes off the top of the intake it could be a low flow do to the fitting on the intake manifold being corroded closing it off

 

Just for an example for you...this morning it was 22 degrees out. After the initial warm up, my heater works so well I end up turning it down to low, and then finally off until it cools off some in the cab. It can become overwhelming if left on high. And this is with a non insulated cab with air coming in from the access holes in the firewall.

Like everyone said already, flush the system and make sure your heater core isnt plugged up.

 

another thought ..... does it have a heater valve? some of the truck models do, and they can get stuck shut, or stuck partway shut.. they are usually just outside the cab near the firewall... If it has a heater valves it is usually cable operated, is teh cable still hooked up??? Things to check!

 

Yea the valve on the inner fender works. All though it doesn't seem like it pumps much water through the hoses. I checked and the core isn't plugged up completely. I hadn't thought about the fitting on the intake being corroded. I tore this heater apart and cleaned it up when I got truck but thats been several years ago. It seems to blow plenty of air it just doesn't warm it up.

 

I've got the same problem in my 67 F100. New waterpump, t-stat, heater core, hoses, heater control valve. I still have to put a piece of cardboard in front of the radiator to get it to blow out hot air and it still won't burn you out of the truck. The only thing thst hasn't been replaced is the radiator and it seems fine. any suggestionswould be great.

 

How about the simplest of things? Radiator cap? If it's not sealing correctly, it will not allow the system to pressurize correctly, and the coolant will not heat up enough. Just a thought.