How-to stop heat from coming out of the lower vents
You just bought your van and you are ready for a great summer of fun. Your A/C is recharged or you are ready to crank down those windows and use the 2-60 A/C (2 windows at 60 mph ? when you feel that something isn’t quite right. You head is cool but your feet are warm, no downright hot! Hot air is coming out of the lower vents in your 82-91 watercooled Vanagon (diesel included). What do you do?
Your problem could be:
The first step is to see what is going on. Put the heater valve in the full closed position (2nd lever down, and move it all the way to the left). Now check the position of the lever on the valve. The diesel Vanagons have the valve conveniently located behind the glove box. Simply open the glove box and allow it to flop to the floor and you will see it. The waterboxer Vanagons have this valve less conveniently located under the van over the spare tire. Remove the spare tire and crawl under on your back. Now look up. See it?
The lever should be all the way at the end of its travel. Try to move the lever with your hand. If it moves some more then your linkage is either out of adjustment or bent (happens alot). If it feels like it could move more but the cable is holding it back then the linkage is out of adjustment. You can temporarily move the valve to the shut off position and if this stops the heat then you will not have heat until the next time you move the lever and then the heat will remain on again. This is a temporary fix as you don’t want to have to crawl around under the van every time you want to shut off the heat.
How do you adjust your linkage? Remove the instrument cluster. You will see a screw holding a clip which in turn holds the cable that goes to your heater. Put the heater valve at full closed. Loosen the screw and move the cable housing (black rubber) until you take up the slack in the cable (make take some experimenting to get this right) and retighten the screw. Now move the slider to full heat and back again. Did your valve move to full closed? If so then you have fixed your problem. If not then try again and if you cannot fix it then your cable is probably bad (bent in the past).
If you see that your cable is bent then this is obviously your problem and you should stop fooling around and buy a new cable as the bent one will never be right again.
If everything seems to be moving and closing properly, and you still have heat, then the valve is leaking internally and must be replaced. Use a couple of small wood clamps and some pieces of plastic or wood to clamp the hose before and after the valve (to keep coolant loss to a minimum). Now remove the old valve and put in the new one (hook the linkage before you install the valve on the hoses as this is easier). Test linkage and adjust if neccessary. Voila, c’est fini!
Now you can happily drive across the US without your toe hair becoming singed ?
I have the parts to do this work available:
Heater valve is PN 171819809E
Heater valve control cable is PN 251265473A
I hope this is helpful to folks!
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