Anyone other then me having a problem with the evap case not draining. Talked to Vintage Air rep at a show a while back and he assured me that it wasn't there case it had to be my install. Well the case is installed correct and the drain rubber tube is on a good angle and open and the truck sets on about a 2 inch rake. So I think it is a blockage in the drain area of the case but I have no idea what would happen if I tried inserting something in the plastic tube. Any ideas what is going on in the case in the drain area.

By the way if you really want to drain the case just turn the defrost on and you will have a nice and wet windshield and interior.

Thanks Chuck

P.S. Other then this problem system works just fine, in fact it will freeze you out of the cab (well at least here in Michigan).

 

Regulate your air compressor down to < 5 psi, and blow back thru the hose. That will tell you if it's clear, but if there's a loose piece of plastic or junk in there, you'll likely have to split the case to get it out. Maybe you could use a piece of wire to hook it. Likely a piece of the foam they use to mount the evaporator.

 

You might try pulling a vaccuum on on the drain line...

 

Before I would do that, because to get the unit out and to split the case would be a major pain, I would hole saw a bigger hole in the plastic around the nipple, see what’s there, if that is where the obstruction seems to be, clear and re-plumb some kind of hose nipple bushing (vacuum, pvc) into the plastic.

 

I think the concern with sawing or drilling is it might not be obvious where the evaporator core is -- OOOPS!

 

Not knowing what's in the drain area is my concern. The drain isn't on the bottom of the case it's about a half inch above the bottom and it's a 90 deg elbow which seems to run level with the bottom of the case which doesn't make any sense to me. I drove the truck for about a half hour with the air on this morning (88 percent humidity). Then parked it on my driveway approach (about a 5 deg angles) nose down, left it for about a 1/2 hour nothing drained out.

I agree it seems to be blocked but i just not sure if it's a good idea to stick something in the drain or drill a new hole in the bottom ( that's a really good idea just a little concerned what I will screw up) .

Not that it means anything but this is installed in a 56 F100

Thanks, Chuck

 

Sometimes they use a flapper valve, molded in rubber, to let water out but not cold air. It could be molded improperly, so it doesn't swing freely. Can you remove the hose and see if the fitting unscrews or pops out like a grommet?

 

Not sure i will look in the morning.

Chuck