heat issues on '85 bronco II

[bonedoc]

Hello there,

My '85 bronco II is now having some heat issues, I know the blend door wasn't working right because it would blow warm air even when the temp setting was all the way on cold. Always gave off TONS of heat. Well I just replaced myu blower motor resistor after finding info on that here and restored all my fan speeds. Everything was working fine and all of a sudden last night the heat cut out! Gives off lukewarm air at best, even with the temp setting at highest setting. Blows cold air now when on coldest but don't know if that is just because the hot is cooler. Need to fix because of course we are now having temps in the teens, murphy's law....LOL!!

Any suggestions would be great!

Thanks

 

[belovedb2]

My first guest is to check the thermostat. Is the temp guage getting to its normal position?

 

[bonedoc]

runs a little on the high side

 

[bonedoc]

just put a new thermostat in about a month ago.

 

[BlackBII]

Are both the heater hoses getting hott?

If so, I would suspect your blend door.

 

[B2dangerous]

You have a plugged heater core. A heater core is just a small radiator that is used to radiate heat that over time will plug off due to calcium deposits, crap floating around in a cooling system, colapsed passages or if there has been some kind of stop-leak ever added to your radiator. Not expensive or complicated to fix.

 

[bonedoc]

Would a heater core plug up that quickly? It literally was working fine and a couple of hours later it started. It will probaly be my first thing to check. The cooling system has plenty of coolant and need to check the heater hoses. The blend door on this vehicle...anyone know what the easiest way to check that is? It doesn't sit right behind the glove box like in later model vehicles.
Thanks alot of the info..


Knows enough to be dangerous!!

 

[bonedoc]

okay guys, checked the heater hoses last night, one is hot the other is cold, so it appears the problem is the heater core. ordering a new one. let you know how it turns out.

thanks

 

[belovedb2]

Worked at Ford for 33 years in climate control. Yes the heater core can clog up over time but this happened suddenly. Next thing to check is the blend door. Is there cable still attached. Is the door fully closing in the heat position. With the engine off you should be able to hear the blend door rubbing the side of the heater case. It should have a sound when it hits the full heat position. Even a small gap in the blend door seal will cause big temp results. Could be something stuck in the blend door area. Keep in touch

 

[belovedb2]

Another thought is that the cable might have slipped on the blend door bracket.

 

[bonedoc]

Well it was the heater core. It was plugged really bad at the inlet. What I think happened was the day it started I had just replaced my blower motor resistor and while doing that I moved the heater hoses up out of the way. I think there was probaly a build up or deposits in the hose and moving it and flexing it dislodged them and that was all she wrote. Antway, got the core for $35.00 dollars and about 40 minutes of time it was done. Would of been faste but the two blind screw up close to the firewall were a pain to get back in. Thanks for all the help!