I'm starting to wonder if the heaters in our trucks where just never that great to start with. I've been getting luke warm heat for quite awhile now, even when it's not all that cold outside.

I did a lot of work to the cooling system this past summer, changing out the water pump, heater core, and putting a 190 thermostat in since the housing gasket was leaking and I had to open it up anyway. Since I changed all that stuff, I figured I probably had quite a bit of air in the system. I've parked it on a really steep grade at various angles and burped it out a couple of times. No change.

I started thinking maybe it was the blend door letting some cold air in. I got under the dash and removed the blend door motor. It works fine. I worked the blend door back and forth by hand while I had the motor off, and it moved back and forth freely. The little plastic piece that Heater Treater talks about that goes between the motor and the blend door that breaks all the time was also fine.

I've checked everything with the temp gun, and when the truck is warmed up, the radiator hoses, both heater hoses, all that stuff is up close to the 200 degree mark.

So what else is there? I've replaced the heater core. I've replaced the thermostat. I've burped the system more than once. I've made sure the blend door is working. The fan blows plenty of air, and it changes vents from floor to defrost and all that just fine.

Am I missing something? Or do these trucks just normally not put out much heat? It doesn't seem right, but I can't find anything wrong with it.

 

I had the same problem as you.... the way I seem to have fixed it is:

Disconnect the inlet hose at the coupler in the middle of it. I have no clue why it isn't a one piece hose..... (clamp off the section of hose coming from the intake manifold.)

Disconnect the hose from the steel pipe leading into the water pump. Plug the pipe with a cork, or something similar.

Run water thru the heater core in both directions. When the water comes out clean and clear, do it again, making sure to trap water in the core, and hoses. (don't let it siphon back out.)

Hook up the hoses again, try to lose as little water as possible.

Burp the system on the flat. Top off any lost coolant.

Heater should be MUCH more effective.

 

Ok, thanks for the info, I'll give it a try. Sadly, it's only supposed to get up to 11 degrees today, so I may have to wait to play with the water hose. :-)

 

Yeah, it has been surprisingly warm here, so, I took the opportunity to give it a go. Again..... the heater will cook you out of the truck now. I LIKE it.

 

I have been waiting to do the same thing myself, having the same problem thou.. Only get in the single digits! Or subzero lol.

 

I've been trying to save some coin on fuel, so the truck got parked. Earlier this week, I took my motorcycle to work when it was in the low-20's. Won't do that again anytime soon. Yesterday, I took the convertible, since it gets low/mid 20's mpg. Its a 66 Mustang, and the heater just can't keep up with temps in the teens. So today, I had no choice but to fire up the truck. It, too, struggles with putting out enough heat. I've got a slow leak somewhere, because there is always a small puddle that forms on the ground whenever I let it warm up in the driveway (never after sitting all night).

 

Heck ya! That's what I'm after! The truck fleet we have at work (Fords), will cook your butt right out if you don't turn the heater down within a couple miles of driving, even in this cold weather. If I could get my old dodge to put out heat half that well, I would be stoked.

 

Ya lol I'm even trying to think of a way to rig up some kind of drain hose that goes out under the garage door so I can do it inside.

 

If you have a washer and dryer hookup, screw your garden hose to the hot water tap, and use that. (might have to toss your hose into the bathtub for a while, to thaw it out.

If you don't, go to wally world, or, your local equivalent, and get a waterbed fill kit. it will have an adapter so that you can hook your garden hose to any sink faucet. It will be cold outside, but, running the warm water thru the hose will at least keep your hands from freezing, and it WILL make your heater MUCH more efficient.

 

Wow!! Good idea HeyYou!!! Never thought of that! That was what was stopping me(frozen hoses and sub zero weather) Guess thats what i will be doing tmrw!