heatercore

if you disconnect the two rubber lines coming out of the firewall above the turbo and stick a water hose in one end you should be able to flow water through it. I took my glove box out and felt the lines going in and out of the heater core and both lines were so hot I nearly burned my hand... if the entrance line is hot and the exit is cold, you've got a clogged heater core.

My truck will blow a lot of air but no heat...

I don't know how to check to see if something is broke on the blend door, as the motor moves smoothly as you change the temperature knob?

Is it possible to remove the bottom half of the heater box without removing the dash? What else is there to check?

Lavon
 
LAmiller said:
if you disconnect the two rubber lines coming out of the firewall above the turbo and stick a water hose in one end you should be able to flow water through it. I took my glove box out and felt the lines going in and out of the heater core and both lines were so hot I nearly burned my hand... if the entrance line is hot and the exit is cold, you've got a clogged heater core.

My truck will blow a lot of air but no heat...

I don't know how to check to see if something is broke on the blend door, as the motor moves smoothly as you change the temperature knob?

Is it possible to remove the bottom half of the heater box without removing the dash? What else is there to check?

Lavon
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Id like to get the heater box out w/o taking the dash out at all...... wheres my sawzall :hehe:
 
Dont know about taking the heater box apart installed, but the dash really isnt that bad to take out. I just did evap core and heater core back in august. Take the floor console up, kick panels out, disconnect parking brake linkage, drop steering wheel, remove two bolts at bottom center of dash, then bolts under the windshield. After that you can roll the dash back into the seats and tie it back so you can get at the heater box.

Lavon, do you have a winter front on? On some trucks they just will not blow much hot air with the fronts on for some reason.
 
some heater cores the coolant doesnt have to flow through the core. they have a by pass so the inlet and outlets will be hot on those styles. isnt the temp blend door cable operated on the dodges look for the blend door and see if it is actually moveing when changing temp settings
 
m james said:
lamiller what year truck mines a 02
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mines an 01.5

bosshogg said:
Dont know about taking the heater box apart installed, but the dash really isnt that bad to take out. I just did evap core and heater core back in august. Take the floor console up, kick panels out, disconnect parking brake linkage, drop steering wheel, remove two bolts at bottom center of dash, then bolts under the windshield. After that you can roll the dash back into the seats and tie it back so you can get at the heater box.

Lavon, do you have a winter front on? On some trucks they just will not blow much hot air with the fronts on for some reason.
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I have a piece of cardboard in front of the radiator...

HILLBILLYPRIDE said:
some heater cores the coolant doesnt have to flow through the core. they have a by pass so the inlet and outlets will be hot on those styles. isnt the temp blend door cable operated on the dodges look for the blend door and see if it is actually moveing when changing temp settings
Click to expand...

On the bottom of the heater box under the glove box, I can feel that the bottom of the heater core is hot through the plastic. The temp blend door is operated by a electric motor on the bottom side of the heater box right next to the heater core. I can see the shaft turn all the way around as I turn the knob from cold to hot. What I can't see is if the shaft could be broken in side the heater box and not actually moving the door.

Sounds like taking the dash out is my next Saturday project and I'll just put a new heater core in while I'm in there.

Lavon
 
LAmiller, you may be right about yours. IIRC, my uncle that used to do a lot of these, told me that the door could break, and the only way to tell is pull the dash out and look..
 
weazel said:
LAmiller, you may be right about yours. IIRC, my uncle that used to do a lot of these, told me that the door could break, and the only way to tell is pull the dash out and look..
Click to expand...

I figured... I'll probably just buy a heater core to put in there before I tear it apart. at 270K miles I'm guessing I've got my moneys worth outta this one.

Lavon
 
LAmiller said:
I figured... I'll probably just buy a heater core to put in there before I tear it apart. at 270K miles I'm guessing I've got my moneys worth outta this one.

Lavon
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LAmiller when you do the heater core i would do a evaperator core to.not a bad job i did two within the last month. only pita is dissconecting the A/C lines.
 
Seems to me I remember someone on one of the boards had it happen one time that the shaft coming out of that electric motor had twisted the center out of the door shaft. You could still see the motor turn all the way around, but it would not allow the door to shut all the way and it would suck cold air in all the time, or spit the hot air to the outside or something, just remember the blend door was screwed up and couldnt do its job.
 
last winter i had exact same issue. i had a leaking head gasket been like that for 20k heater would really suck. but you could drop the glove box and both lines to the heater core would scald you? i ended up noticing that if the radiator got just a quart low it would fill the core with air then heat would not work. so you could fill the overflow with water and after you drove truck got it good and warmed up, and let it sit overnight so it would pull the antifreeze in the next day the heater would run you out. $.02
 
If the heater core isn't leaking try this. I did it on the wife's Durango and it worked.
Disconnect the heater hoses. Pour radiator flush stuff in one hose until it comes out. Go drink a couple beerz.
Drain flush crap out, flush with clean water, i also hooked up an air line and blew all the brown crap out. Now the wife has heat, she's happy, I'm happy. Oh ya i did this last year still works.
 
Well I tackled the project of changing my heater core this afternoon and have AWESOME heat now!!! Cost me $58 for a core at Advanced Auto Parts and took me exactly 4hrs from the time I pulled it into the shop Until I had it together and on the way back home.

My advice would be to definitely get the core from Advanced since the lines coming out of the core swivel and I didn't even have to loosen my HVAC box... I had to fight it to get it in but way easier then to disconnect the A/C lines and all that goes with loosening the box.

The old core still circulated fluid but the corrosion in the fins was so bad, the air could not blow through it.

I had HOT air blowing out of the vents before the needle even moved on the temp gauge... It was definitely not near as bad as I anticipated it to be!

Lavon
 
How the Flock did you get that in there without pulling the box?
Tell us the secret, I changed my core and evap at the same time.
 
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