Heat still isn't working, will only blow luke warm air

[BoostedAWD91]

Ever since i bought my Galant years ago, the heat just never really worked to well. The best it will do is blow luke warm air out of the vents. Figured it was the heater core so i bought a aftermarket one and replaced it... Still didnt work. After my buddy totalled his galant which had amazing heat, i took absolutley everything from his car to try and get my heat to work. I used his OEM heater core, blower motor, resistor, all the controls, all the heater hoses were replaced in the engine bay during the rebuild and still it won't work. Just blows luke warm air and you have to put the blower on full blast to really even feel it, like the first two settings really dont seem to do to much. I have changed thermostat's a few times while i had the car which didn't make any difference either, my coolant temps are at 180 degrees at FOT, even if it starts to clime up to 200-220 degrees, it still doesn't get any warmer.
I am just completely out of ideas and just plain stumpted.

 

[turbowop]

503 is kind of similar. It's warmer than luke-warm, but doesn't get hot. I have to keep the temp control at full hot to get anything remotely warm. I was beginning to think that maybe the temp control isn't moving it to full warm, but I dunno. It works well enough that I don't worry about it that much.

 

[omertaitalia]

same issue here, every things hooked up and its only look warm.

 

[DR1665]

That's strange, man. Could it be one of the linkages isn't fully closing the flaps to seal the heater/fan box, allowing cold air to dillute the hot? The two large flaps also have foam insulation ln them which disintegrates over time. What about any seals around the unit where it mounts into the rest of the underdash HVAC system?

If the heater core is hot, but cold air can enter the system afterward, you'll never get hot air. Weatherstripping, ya know? Good luck.

 

[BoostedAWD91]

yeah i checked the function of all the linkage and everything is opening and closing correctly

 

[gramkrakr89]

plugged t-stat housing tap? plugged return pipe?

does your coolant temp regularly get over 200-220?

 

[holeshotmoe]

With the car warmed up, grasp each of the heater hoses and see if they're the same temp. If you're not getting circulation, one will be much cooler than the other. Full coolant flow will cause both to be hot. If one is hot and the other much cooler, disconnect both from the core at the firewall and connect together with a piece of 1/2 inch pipe, tighten the clamps and try it again. You said the core is good, so if the supply and return are not both hot then there is some obstruction between the two. If they're both hot, then make sure the ventilation and temp control cables in the dash are not crossed up. I did this once. The temp control cable should connect here:

IIRC you can check this area easily by removing the panel on the left side of the console, near where your right calf is while driving. Rotating the temp knob while watching will tell you. If it is correct, then follow instructions for reconnecting it (from pg 55-27 in the electrical manual), pasted here:


Make sure the outer jacket is removed from the pinch clamp when you connect the inner cable loop to the end of the arm, rock the arm down while the control knob is in the cold(est) position, then press the cable jacket into the pinch clamp.
Also, guess I should have first asked: Is your fan motor blowing full force? That is, is the problem that the fan won't blow or is it that your're not getting hot coolant/air circulation?

 

[curtis]

I had a nissan like this once. I chucked up a piece in the lathe at work turned it down to the od then cut a long taper in it on each side with a 1/4 inch hole in the middle. Then inserted this in the hose leaving the heater core so the water slows down and the heat is removed from the water. Worked like a charm after that. Mustangs have a similar thing from the factory just a steel insert with a rubber washer in the middle with a small hole in it. Used in them to keep pressure spikes from damaging the heater core. Hit a local junkyard and just squeeze the heater lines on any of the 5.0 or 4.6 cars and you'll find one.

 

[Barnes]

Curtis: But if OEM these cars put out great heat, why would he need this?

 

[tsitalon1]

heater core is clogged!

 

[gramkrakr89]

Quoting BoostedAWD91:
... After my buddy totalled his galant which had amazing heat, I took absolutley everything from his car to try and get my heat to work. I used his OEM heater core, blower motor, resistor, all the controls, all the heater hoses were replaced in the engine bay during the rebuild and still it won't work. Just blows luke warm air and you have to put the blower on full blast to really even feel it...



unless the core clogged sometime in between his buddy totaling his car and the install, i doubt it.

well, I guess it could have picked up a bunch of gunk from a clogged radiator if he failed to flush the system out before installing...

something sinister is afoot here... /ubbthreads/images/graemlins/uhh.gif
I suspect a clog at the T-stat housing somehow!

 

[Wizardawd]

With the car running at temp and the heat on, try feeling the heater hoses under the hood. If they are both hot, you have good flow in/out of the heater core and its something else in the box. If one is hot but the other warm, heater core. If both are warm but not hot, you have a coolant flow issue in the system itself (water pump, heater pipe, etc).

Wiz

 

[BoostedAWD91]

my coolant temps are pretty much always at 180 degrees. The really weird thing i found last night is with the heater on full blast and when i open my glove box, there is a ton of cold air being blown in /ubbthreads/images/graemlins/dunno.gif All the heater hoses are hot at operating temp so the heater core is getting hot coolant flow. I have flushed my system numerous times so i know its not clogged and i even blew out the heater core to see if it was clogged which it wasnt. Im not sure where all the cold air from the glove box is coming from. There is not heating ducting leaks or anything.

I mean its not the biggest problem in the world that im not getting hot heat out of the vents, it just more so bothers me that i can't figure out why im not.

 

[BoostedAWD91]

Quoting curtis:
I had a nissan like this once. I chucked up a piece in the lathe at work turned it down to the od then cut a long taper in it on each side with a 1/4 inch hole in the middle. Then inserted this in the hose leaving the heater core so the water slows down and the heat is removed from the water. Worked like a charm after that. Mustangs have a similar thing from the factory just a steel insert with a rubber washer in the middle with a small hole in it. Used in them to keep pressure spikes from damaging the heater core. Hit a local junkyard and just squeeze the heater lines on any of the 5.0 or 4.6 cars and you'll find one.



Do you have a picture of what this looks like by chance?

 

[SleepinGVR4]

Quoting BoostedAWD91:
my coolant temps are pretty much always at 180 degrees. The really weird thing i found last night is with the heater on full blast and when i open my glove box, there is a ton of cold air being blown in /ubbthreads/images/graemlins/dunno.gif All the heater hoses are hot at operating temp so the heater core is getting hot coolant flow. I have flushed my system numerous times so i know its not clogged and i even blew out the heater core to see if it was clogged which it wasnt. Im not sure where all the cold air from the glove box is coming from. There is not heating ducting leaks or anything.

I mean its not the biggest problem in the world that im not getting hot heat out of the vents, it just more so bothers me that i can't figure out why im not.




Chris it sounds like the foam around the blower motor and heater core box is deteriorated and is letting cold air in.

 

[BoostedAWD91]

did i just take your heater core, or did i actually take your entire heater core box

 

[SleepinGVR4]

I can't remember

 

[curtis]

This is a 4.6 one

Read

This is the 79-95 one


It really helped with the nissan, I personally like hot weather so me lossing the ac was really no big deal in mine but I be damn if I'll ever remove heat from any car.

 

[Barnes]

Again, Curtis, you have yet to answer my previous question: If a stock GVR-4 puts out plenty of heat, why would he need to add a restrictor?

 

[BoostedAWD91]

i agree curtis, i never use a/c in the summer so i could care less about having that, i prefer all windows down for my A/C, but as far as heat, i can't go without it and i have not driven my galant as much in the winter as i like to just because of the fact the heat sucks. I mean i have seriously tried everything to get the heat to work better, but nothing helps