Heater/AC vent problem

[mrluhman]

I put a new heater core in my truck and ever since the vent settings are functioning wrong.

For instance the "vent" setting blows only through the floor vents and the "defrost" setting blows air through the midlevel vents where the "vent" setting usually blows. I didnt think it was a big deal until the first rainy day when I had no defrost. Its like all the settings are off by one.

Is there something I could have done during the heater core installation? Could it be something in the unit in the dash? It was working properly before so I am guessing it is something I did and not a mechanical issue.

Thanks in advance gents.

 

[katugly]

Make sure the all the vac lines are hooked up to the actuators. After you make sure that they are hooked up take off the cover on the vent box to make sure your doors are moving like they should. For your Defrost door you need to remove the lower diffuser and stick your hand up in there and feel if the door is dropping down. There are a couple of plastic pieces that are sometimes broken but don't look like it when the doors are shut.

This door if broken will shut off air flow. I think it defaults open which is closed on the defroster side.

 

[Cornfield creations]

Yeup those pieces break a lot. When I actually changed mine, and didn't realize that a vacuum line rotted off the top on an actuator. Never worked right until I had to replace it a year later due to other issues.

 

[mrluhman]

Sweet thanks guys!

I am working at the state fair booth until Sun but I will teat into it again next week. The pic helps quite a bit. I figured it might be something like that and probably not mechanical.

 

[Teck]

Joe it"s not all that complicated, most of it is vacum operated, you probably didn't get them all hooked back up right. Rebuild all mine when doing the interior so maybe I can still help.