My van is leaking, I'm told the drain for the vent up front is plugged up, I believe it can be accessed by removing the passenger fender, but I really don't want to be removing body panels, shouldn't the tube hang down on the passenger side below the van? I have searched the internet and found no photos or diagrams for this on a van, tho I know there is a drain, all vehicles have them.

 

Hi Mapes,
I replaced all the parts on my AC 6 years ago and had the to remove the blower fan housing to get to the evaporator. my 88 is the same as your 89 and the drain is on the bottom of the blower fan housing under the hood. Mine did not have a drain hose or what I think is called a "duck bill tube" on it. A duckbill fitting is one that opens to let the water out but is closed off so bugs and dirt do not get inside the housing. When I reinstalled the bower housing, I used a piece of clear tubing and a hose clamp over the short nipple that sticks out for the drain. I just added enough hose so that the water would not run down the inner fender wheel well.
Here is a pic where I believe the drain is.

-
This next pic is of a 85 case which is different from ours but shows the drain tube with a "duck bill"

-

My AC compressor has a bad front seal and the AC clutch looks like it might have gotten hot. I will be replacing the compressor with clutch and evaporator here in the near future so I will have to remove the fan case again. I was also having trouble last year with water puddling down in the foor board on the passenger side when the AC was running. I am not sure that it is the drain stopped up though. the hvac case is in 2 parts. The inner which has the heater core and evaporator core. The other is the fan case under the hood. in the drawing below you can see how they mount on each side of the firewall with a thick foam gasket between the firewall and case so seal it. Not long ago someone posted about finding the firewall badly rusted once they removed the fan housing. That would happen if the foam seal between the firewall and housing was not sealing properly and allowing water to drain down the firewall.

 

How about the vent below the windshield where the air is drawn in from outside, where does it drain?

 

The cowl drains out between the junction with front fenders and the firewall (cowl panel)
Your front evaporator and heater case drain is a rubber tube sticking out the body below the HVAC case
They do plug up with leaves and debris sometimes
You will have to get under the vehicle and look straight up below the case
Pretty hard to see the tube any other way
Fairly easy to clean out once you get your fingers on it
Good luck

 

Thanks, I hope this is all, I fear it has rusted and will forever leak inside, the reason the entire front floor required replacing, previous owner thought it was the windshield, so he damaged the frame around it, I had it fixed, but water still enters, so I got my sprayer and started hosing the vent up front, sure enough the water started running in my new floor, may need to find someone to pull the wipers and remove the top to seal it back up.