What happened to the Beetle's heater

On a late model Beetle last night I was driving down the freeway and
it was cold outside. For a good half hour the heater stopped
working. No air would pass through the vents at all no mater how many
times I moved the heater control knob up and down. The hot air would
not go. It just stopped all of a sudden when I had the heat on half
way. Then by the end of the road trip the heater returned back to
normal. What happened? The heater is purely mechanical. All it is,
is a lever that opens up a little door inside the heat exchange
tubes. It's got a cable that runs to it. The cable wouldn't just
break and fix itself in 1/2 hour would it? So what would prevent the
air from passing through?

wrote:

> On a late model Beetle last night I was driving down the freeway and
> it was cold outside. For a good half hour the heater stopped
> working. No air would pass through the vents at all no mater how many
> times I moved the heater control knob up and down. The hot air would
> not go. It just stopped all of a sudden when I had the heat on half
> way. Then by the end of the road trip the heater returned back to
> normal. What happened? The heater is purely mechanical. All it is,
> is a lever that opens up a little door inside the heat exchange
> tubes. It's got a cable that runs to it. The cable wouldn't just
> break and fix itself in 1/2 hour would it? So what would prevent the
> air from passing through?


1) Blocked air inlet to fan. Often, the tarboard will fall into the inlet.

2) Mouse nests.

3) Flaps disconnected or "flapping" around.

4) Fan belt slipping.

??

Speedy Jim
http://www.nls.net/mp/volks/

On Sep 23, 5:09*pm, "
> wrote:
> On a late model Beetle last night I was driving down the freeway and
> it was cold outside. *For a good half hour the heater stopped
> working. *No air would pass through the vents at all no mater how many
> times I moved the heater control knob up and down. *The hot air would
> not go. *It just stopped all of a sudden when I had the heat on half
> way. *Then by the end of the road trip the heater returned back to
> normal. *What happened? *The heater is purely mechanical. *All it is,
> is a lever that opens up a little door inside the heat exchange
> tubes. *It's got a cable that runs to it. *The cable wouldn't just
> break and fix itself in 1/2 hour would it? *So what would prevent the
> air from passing through?
--------------------------
> On a late model Beetle last night I was driving down the freeway and
> it was cold outside.

You said 'late model'. By that do you mean a 1968 thru 1979 VW
Beetle or one of the new Beetle's with a water cooled Golf type of
engine?

Anyway, this might be of some help:
http://www.vw-resource.com/heat4.html#schools

A point to keep in mind is that the stock VW heater is a single-pass,
flow-THROUGH design. That is, there must be some OUTLET from the
cabin before heated air will flow INTO the cabin.

On early bugs you had to crack a window. On later models they added a
vet to the rear-side windows. On the Transporter there was usually
enough leakage around the controls to give a pretty good flow although
this was compromised if the lower body panel was removed. Nowadays
most of us simply leave one of the wind-wings cracked.

But if your vehicle has a vent you might want to check that it isn't
being blocked by... whatever.

-Bob Hoover

hmmm a Beetle so tightly sealed that more air can not enter or more air
pressure can't be created!
Been a while since I had seen one of those! lol

Excellent point since it makes very good sense! ;-)

"Bob Hoover" > wrote in message
...
>A point to keep in mind is that the stock VW heater is a single-pass,
> flow-THROUGH design. That is, there must be some OUTLET from the
> cabin before heated air will flow INTO the cabin.
>
> On early bugs you had to crack a window. On later models they added a
> vet to the rear-side windows. On the Transporter there was usually
> enough leakage around the controls to give a pretty good flow although
> this was compromised if the lower body panel was removed. Nowadays
> most of us simply leave one of the wind-wings cracked.
>
> But if your vehicle has a vent you might want to check that it isn't
> being blocked by... whatever.
>
> -Bob Hoover