heater blowing cold air?

[made2drag]

for some reason my heater isnt blowing hot or even warm. its an 86 custom delux with a/c. when i got the truck i assumed it was just a bad thermostat, so i changed it out and still no heat. i can let it run for 30 mins and my temp shows 190 or so. any one have any trbl like this and found the fix? thanks

[Stepper86]

Might be a clogged up heater core, they can get quite nasty inside. Or the vent doors in the box not working right.

[made2drag]

Originally Posted by Stepper86

Might be a clogged up heater core, they can get quite nasty inside. Or the vent doors in the box not working right.

oh, ok..didnt think about the blend doors not opening, thanks!

[made2drag]

must be one or the other, i think i read somewhere the copper heater cores are the ones to get and they are only $30, so if the blend door is working fine i will change the core. the core could be the original. thanks stepper 86

[crazeetxn]

Unhook the hose from the heater core to the radiator and see if there is any return. If your coolant level is down, that'll be a problem too.

There are two flaps in the box. One is the blend door and the other is the one that adjusts for the heat. If there is air coming out of the vents, then your blend door is fine and it may be the door that adjusts for your heat.

Drop your glove box and see if the cable moves when you move the selector level from cold to hot. May just be your cable isn't moving the heater door.

[Breadman]

At running temp.you can feel the heater hose's going in and coming out of the
heater core. Both should be hot. If not the core is stopped up.

[motornut]

have a look here

[crazeetxn]

Originally Posted by Breadman

At running temp.you can feel the heater hose's going in and coming out of the
heater core. Both should be hot. If not the core is stopped up.

Yeah, guess that way would be easier...LOL

[made2drag]

THANKS GUYS!

i will check it out this weekend....will let you all know what i find.

[made2drag]

i have a feeling its the rod that motornut says gets bent or broke. i do remember when i going from cold to hot the selector knob would slide to hot but spring back a few inches and wouldnt stay in the hot position all the way. must be keeping a door shut or something. if i was at home right now id go look, but its going to be tomorrow before i can check. my son Dawson's birthday party is tonight. 4 years old!

[76stepsidechevy]

Originally Posted by made2drag

i have a feeling its the rod that motornut says gets bent or broke. i do remember when i going from cold to hot the selector knob would slide to hot but spring back a few inches and wouldnt stay in the hot position all the way. must be keeping a door shut or something. if i was at home right now id go look, but its going to be tomorrow before i can check. my son Dawson's birthday party is tonight. 4 years old!

mine does the same thing when going from cold to hot and ive got lukewarm heat. might be on to something here. The heat is ok when its 50 or so out but any colder than that and it takes a while to get the truck warm inside. I also had rotten foam blowing out the vents for a while, im guessing a seal off the blend door? im sure thats not helping.

[made2drag]

it ended up being the the rod that motornut says gets bent or broke. i had to adj mine because when i moved it to hot it wasnt moving the rod all the way.....now i have HOT heat...thanks guys

[motornut]

Yup heat is good, found my winter grill cover this weekend
Been very mild here still , but it sure helps me for heat
easier then changing thermostats, some times it's the mix that doesn't let it heat up
Posted via Mobile Device

[made2drag]

Originally Posted by motornut

Yup heat is good, found my winter grill cover this weekend
Been very mild here still , but it sure helps me for heat
easier then changing thermostats, some times it's the mix that doesn't let it heat up
Posted via Mobile Device

thanks, it's nice and toasty now