Air vent stuck on defrost

[Frank4]

My air vent while the engine is running is stuck in the defrost positions and will not blow through the vent any ideas on how to fix?

[TURBS]

Originally Posted by Frank4

My air vent while the engine is running is stuck in the defrost positions and will not blow through the vent any ideas on how to fix?

You need a new vent motor/actuator.


Turbs

[VinceU]

Originally Posted by Frank4

My air vent while the engine is running is stuck in the defrost positions and will not blow through the vent any ideas on how to fix?

Maybe you can locate the vacuum diaphram motors and lube the acuator shafts. While under there with engine running, have another operate the controls for vent system and check for vac leaks.

[TURBS]

Originally Posted by VinceU

Maybe you can locate the vacuum diaphram motors and lube the acuator shafts. While under there with engine running, have another operate the controls for vent system and check for vac leaks.

I believe it to be all electronic no vacuum.
Could be wrong tho.

[cfsoistman]

Is your set-up an Evans? If so here's their website with their products should you need parts. There's a troubleshooting area as well.

Evans Tempcon, Inc

[cfsoistman]

Evans Tempcon, Inc Troubleshooting

Does any of these look like you set-up? This is the link directly to the troubleshooting section.

[cfsoistman]

http://www.evanstempcon.com/pdf/dzsb/vacuumtsg.pdf

Checkout #2

[VinceU]

Originally Posted by cfsoistman

http://www.evanstempcon.com/pdf/dzsb/vacuumtsg.pdf

Checkout #2

Great reference Charlie, couldn't recall vent system maker.

[ridersfan]

Typically when there is a vacuum leak, you will only have defrost, unless it's a purely electrical system. Having electronic controls does not make it a purely electrical system. If it's OEM to the chassis, and not from the upfitter, it's probably vacuum

[Frank4]

Thanks for all the info, I have not had the time to go out and work on it. Sounds like a vac problem. Dose anyone happen to know where behind the dash the lines and vac are located?

[VinceU]

Originally Posted by Frank4

Thanks for all the info, I have not had the time to go out and work on it. Sounds like a vac problem. Dose anyone happen to know where behind the dash the lines and vac are located?

The "Vac" is developed by the engine intake manifold. Usually it - feeds a small volume chamber for the vent system. You need to spend a little time moving stuff around under there. You'll see hoses leading to a distribution box, thats where the valves will be with small vacuum hoses on each valve. Another to change position of controls while you watch/listen.

By the way, vehicle codes mandate the system must default to defrost in case of failure. Allows driver to see in bad weather. Problem could be large leak in vac supply or even severely crimped hose, happens when rubber ages, esp in engine compartment.