Blend door failure

[Baseranger]

my blend door isn't working like ford wanted it to. I am looking at the motors available for it, and it asks if I have automatic or manual ac controls. I have knobs on the dash that I turn to make things happen, does that mean I have a manual system? I would hate to get the wrong one, because electrical crap can't be returned.

 

[Legend]

If you use one of those knobs to set a temperature and the heater or a/c runs just a little or very hard as it needs to in order to maintain the temperature, then it's automatic.

If you use one of those knobs to make the temperature of the air coming out hotter or colder and another knob to get just a gentle breeze or a blast of air and it continues to run like that regardless of how hot or cold it is in the cabin, then it's manual.

To put it another way:
With automatic, you set the temperature you want, hot, cold or somewhere in between and the heater or a/c will run as hard as it must to maintain that setting.

With manual, you set how hard the heater or a/c is running and it will keep running at that level, regardless of how hot or cold it is.

 

[Earl43P]

http://www.therangerstation.com/Magazine/Summer2009/blend-door.htm

^ That's a 97's write-up.

http://www.therangerstation.com/Magazine/winter2007/1998_heater_core_replacement.htm


You'l need to pop the glovebox door to see which actuator drives your blend door, but it's likely got the broken drive tab, not a bad actuator.

Read this: http://www.blenddoorfix.netfirms.com/

 

[shane96ranger]

it's likely got the broken drive tab, not a bad actuator.

I agree. The tab is the weakness.

 

[Baseranger]

I looked at it today at school, and it is the door itself. The actuator is working like it should. Max ac is the only cold setting, all the rest are thru the heater core.

 

[noahkenny]

I am a heavy equipment mechanic and I work for the local Cat dealer in Alabama and this is the exact setup in most Cat machines. Probably made by the same a/c manufacter. I believe these are built by red dot. And they suffer the exact same problem. Broken blend door tabs. At least Cat was smart enough to start putting steel rods running the length of the blend door instead of just all plastic. The electric actuators, the way the are geared create a tremendous amount of torque. Alot of times the stops that are built into the electric actuator to limit how far it can turn, one will break off and that is what cause the door failure. So save yourself some head ache and make sure that the actuator will only turn so far either way because if you replace the blend door with a broken actuator stop then then new blend door will be broken within a week or two.

 

[Baseranger]

I figured that I will just pull it out and figure out how it's design doesn't work, and take care of that. I don't want to have to fix it every couple of weeks.