I have experienced the heating problem described and fixed it by
installing a new stock 87 degree thermostat. Most people think of the
thermostat as there to keep the engine from running too hot but it
really is there to keep it from running to cold. That is what mine was
doing when the thermostat was acting up, running so cold on cold days
that the heater had no heat at times. Up a long hill the heater would
crank great and then down the other side it would drop, as the temp
gauge dropped way down as well.

First question, how is the temp gauge behaving? Driving down the highway
does it read about the same on warm and cold days? If it drops much
lower down long hills or on cold days you probably need a new one. If
you live in a warm climate you can drive a long while without realizing
you have this problem.

Mark

Mark Tuovinen wrote:

> I sympathize with you on this issue, only it has been sub zero here lately.  My 87 Syncro GL has been less than generous with the heat making for a cold ride to work and even colder one home.  As Mark Drillock has already suggested start with replacing the thermostat and see how that helps.  I am going to do mine this weekend now that is has warmed up to 15F.  Someone recently posted about building a partition behind the front seats and using ducting to get heat from the rear heater to the front.  I half considered this but thought that the kids might complain if I took their heat away.:>)
>
> Mark in AK
>
> ----- Original Message -----
> From: Andy Highland <andy@420.AM>
> Date: Tuesday, November 28, 2006 11:55 pm
> Subject: Front heater: low heat at highway speed
> To: vanagon@GERRY.VANAGON.COM
>
>
>>I've been using my van (1990 Westfalia) in sub 40 F temperatures for
>>the first time. When I'm at freeway speeds, the heater is blowing
>>cold air. When I close the floor vents, (3rd lever pushed to the
>>right) the air gets a little warmer, but not by much. Basically, the
>>heat coming out is totally inadequate, but only when going fast in
>>cold weather. In more moderate temps, or when I'm on city streets it
>>seems OK. So is my front heater broken, or is this how other people's
>>vans work? I find it hard to believe that people up north could live
>>with such a pathetic heater.
>>
>>Thanks,
>>andy
>>
>
>