Bronco Forum - Full Size Ford Bronco Forum banner

1 - 20 of 23 Posts

·
Registered
Joined
·
566 Posts
Discussion Starter #1
and guess what, its now blowing out colder air!?!?!?!?! The water temp goes up to normal and stayes like normal, so I relaly dont know what else it is.

I checked the old one, it looked to be the original one. It had some dings and stuff on it.

ok heres what I've done so you can rule them out.

New:
thermostat
upper hose
lower hose
both heater core hoses

flushed the radiator and heater core when I did the thermostat a week ago. Coolant looks great! Both Heater hoses are hot! So im getting only cold air now makes no damn sence?

So I ask what is left now!!!!!

Funny how this summer everything worked fine, it blew heat out HOT! And now its NOT?
HELP!
 

·
Try it now!!
Joined
·
9,125 Posts
Work backwards from the heater core. Put your hand on the heater hoses and see if they are hot, not hot, or only one is hot?

Follow the hotness up to the heater core. Take off the cover and see if the heater core is hot. If the heater core is cold, its not getting coolant, but you will know that already since the hoses will be cold.

-Will
 

·
Registered
Joined
·
566 Posts
Discussion Starter #3
checked!

Both the hoses going to the heatercore are literally HOT!!!!!
So I don't know what that means.

I heard something about the heatercore door maybe have gotten stuck and is just letting the cold air go throught by instead of blocking it and letting the warm air come in. If that maybe the case do I have to pull ouf the whole dash to then take a look at this?? Anyone ever done that before on a Bronco??
 

·
Registered
Joined
·
2,662 Posts
BuckingBronco93 said:
checked!

Both the hoses going to the heatercore are literally HOT!!!!!
So I don't know what that means.

I heard something about the heatercore door maybe have gotten stuck and is just letting the cold air go throught by instead of blocking it and letting the warm air come in. If that maybe the case do I have to pull ouf the whole dash to then take a look at this?? Anyone ever done that before on a Bronco??
Two hoses hot means water is flowing from one hose through the heater core and out the other. Its like the human ciculatory system, leaks are bad and things genrally flow through in one direction.

You should have heat assume your door is opening. Do a search and you should find something.
 

·
Lick my balls
Joined
·
13,048 Posts
Did you reconnect that cable going to that vent door, after replacing your heater core? It is something simple, Just back track over everything youve done to your truck since the heat stopped working. You're bound to find the problem. I'm sure too, it WILL be something simple you just overlooked.
 

·
Registered
Joined
·
3,425 Posts
steve83 will ahve good knowledge on this...i believe there is a resistor or something there...it is what determines the temp(as to how you set it in the cab)
look here http://fullsizebronco.com/forum/showthread.php?t=54077&highlight=burn+leaves

that should be it we have rulled everything else out.. take a look at it and if nothing is obviusly wrong then replace it...if i had to guess your problem lies within the temperatture control...aka the truck is not thinking to blow hot air

DC
 

·
Try it now!!
Joined
·
9,125 Posts
The blend is controlled manually by a cable and a door, no resistor involved. The only resistors are for the blower motor settings.

Sounds like the door isnt moving from cold to hot.

Take off glovebox, check cable. If attached, pop open the heater cover and check to see if the heater core is hot (it will be) and watch the blend door for movement as you operate the temperature cable.

-Will
 

·
Ex Navy Nuke
Joined
·
5,422 Posts
This happened to me before and my brand new HC was partially clogged. Coolant was only passing thru half of it so half the air was hot and the other was cold so the result was cold interior. Pull the cover off the HC and with the engine warmed up and running with the heat on high and the blower motor on high put your hand on the HC and see if it blows hot thru part of it and not the other part. If this is the case then you too have a partially clogged HC.
 

·
Registered
Joined
·
566 Posts
Discussion Starter #9
kf4amu said:
The blend is controlled manually by a cable and a door, no resistor involved. The only resistors are for the blower motor settings.

Sounds like the door isnt moving from cold to hot.

Take off glovebox, check cable. If attached, pop open the heater cover and check to see if the heater core is hot (it will be) and watch the blend door for movement as you operate the temperature cable.

-Will
thats what im thinking now. I'll pull that cover off and check it. New heatercore is in so it can't be clogged allready? Also the only wire I pulled off was that tiny cable located on top of the heatercore. Its still attached it simply snaped into that spot, im guessing the door is just stuck, I hear on older vehicles its commone for that door to stick. I'll check is out in a few tomarrow.

Sounds like a simple fix, I also heard waterpump maybe? but highly doubt that since the temp gauge works weel and not over heating.

now that I remember, if the door is controlled by that cable, im thinking yeah that door was shut then. but when turing the hot/cold gauge nothing happens
 

·
Banned
Joined
·
33,450 Posts
Sounds like you didn't reconnect the cable to the blend door lever. From what you said, I get the impression you just clipped the cable sheath to the top of the duct.
 

·
Ex Navy Nuke
Joined
·
5,422 Posts
Did you not listen to me? What do you mean can't be clogged already? The one I had was clogged from the factory. It's a real quick check to do what I said and make sure that it's not clogged. It took me a long time to figure out the problem, just trying to help you find it sooner if you have the same problem as I did. The other opinions here are also very plausible and good advice but I'm just giving you one more thing to check.
 

·
Registered
Joined
·
1,864 Posts
A while back the local parts guy had a batch of brand new heater cores that were bad. The way I first found out was when I was just fooling around with one..........I blew smoke into the one side, and put my thumb over the other nipple.....there was like three places in the heat exchange grid that the welds/solder was all boogered up and I seen smoke coming out. If I would have installed one of them....it would have failed shortly afterward, or immediately.

My point is this.....just because a part is new or rebuilt....DO NOT trust it 100%.

On the other hand if both hoses are hot then there is flow through the core.....your problem is either in your blower motor or divert door IMHO.
 

·
Ex Navy Nuke
Joined
·
5,422 Posts
Streetgang said:
On the other hand if both hoses are hot then there is flow through the core.....your problem is either in your blower motor or divert door IMHO.
NO! If the HC is partially clogged, then both hoses will be hot. The problem will be that only part of the HC is getting hot so all the air passing through it doesn't heat up. Some air gets hot and some stays cold = warm at best.
 

·
Banned
Joined
·
33,450 Posts
If the HC is wide open, both hoses will be hot because the water will flow so fast that its temp won't drop much as it rushes thru the HC.

If it's totally blocked, only 1 hose will be hot - the other will be cold, because the air from the blower will bring the water to ambient temp.

If it's partially blocked, you'll have 1 hot & 1 warm because it'll be between the 2 conditions above.
 

·
Lick my balls
Joined
·
13,048 Posts
There a vacuum module that controls the heater operations. I have one that is located in the pas side of the engine compartment right below the hood hinge. Maybe the vacuum hose came off, or like mine the mechanical part became disconnected.
 

·
Try it now!!
Joined
·
9,125 Posts
waltman said:
There a vacuum module that controls the defrost operations. I have one that is located in the pas side of the engine compartment right below the hood hinge. Maybe the vacuum hose came off, or like mine the mechanical part became disconnected.
There, fixed that for ya

:thumbup
 

·
Registered
Joined
·
566 Posts
Discussion Starter #19
BUMP,
yeah both hoses are hot even when the heater blower motor is barely on they hoses get hot, when on full blast they are hot too they're both hot all around. but I have no heat. I assume its the heatercore door and will just check that out saterday.
 
1 - 20 of 23 Posts
Top