Date: Thu, 7 Jan 2010 14:37:59 -0800
Reply-To: Scott Daniel - Turbovans <scottdaniel@TURBOVANS.COM>
Sender: Vanagon Mailing List <vanagon@gerry.vanagon.com>
From: Scott Daniel - Turbovans <scottdaniel@TURBOVANS.COM>
Subject: Re: No heat at stoplights.
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re
"Now add a
> "tired" pump with worn or eroded vanes '
I was going to add, if considering the w. pump vanes, one must also consider
the surface that those vanes are near - the 'impeller surface' I'll call it.
If that's all corroded to hell, you could have poor water pump performance.
I have not seen the impeller surface badly corroded in waterboxer engines,
but it is part of the engine block. You'd have to remove the water pump to
inspect properly. It's not likely, but it needs to be at least considered.
Insulating the heater hoses under the van helps heater performance.
Make sure the rear heater is off, if desiring more front heater performance.
A few vanagon owners are unaware of the rear heater valve under the back
seat. I was shocked actually, when I saw that VW did it that way, a mostly
unmarked heater control under the back seat.
I don't know that there actually is an 'recirculate interior air' feature in
the vanagon heater system.
and what is the *actual* temperature of the coolant in the engine ??
IR Temp gun is your best freind for something like this problem :
Make sure engine coolant is at least about 180 F.
measure the temp of the heater hoses lettering the heater core, ( underneath
above the spare tire ) , make sure those are nice and hot ( 150 F say,
measured there, would not be good ) . ,
Measure the temp of the heater hose after the heater core, to see how much
heat is being removed by the heater core. If the temps are pretty close,
then it would indicate the heater core is clogged with junk, or for some
reason inefficient. And you need good hot coolant to the heater core in the
first place of course . I haven't seem to see much of it lately, but for a
long time I felt it was very common for vanagons to be running around
running too coolly. Cooler is not better, warmer is, winter and summer.
You want the engine running fully up to temp, all year long, and in winter,
it's really important, of course.
Scott
----- Original Message -----
From: "Jeff Palmer" <jpalmer@MTS.NET>
To: <vanagon@GERRY.VANAGON.COM>
Sent: Wednesday, January 06, 2010 7:21 PM
Subject: Re: No heat at stoplights.
I iike that answer. I'm pretty sure I didn't drive with a bad thermostat,
low coolant and air pockets for all 16 years of van ownership. Maybe 10
years but not all 16 :)
Try your rear heater - it will likely blow heat at idle (mine does). -30
weather can take a lot of heat out of coolant over 6 feet of travel.
Jeff
On 2010-01-06, at 1:13 PM, Don Spence wrote:
> Think about it. The engine is way in the back, the heater is way in
> the front. The transfer tubes from rear to front are exposed to the
> elements and share their captive heat with the radiator. (which
> transfers heat to the external air mass.) So, the heater core is
> disadvantaged from the beginning.
>
> The heater has a fan blowing cold air across the heater core
> (assuming you are set to outside air and not recirculating inside
> cabin air which would slightly lessen the situation).
>
> At idle the water pump is providing minimum flow hence minimum hot
> water available for heat transfer in the heater core. Now add a
> "tired" pump with worn or eroded vanes and you get even less flow and
> less heat to transfer. If the fluid is barely moving through the
> core the latter will quickly cool and blow cold. Pick up the revs
> and you do two things. Add more fuel to the fire (gasoline) and pump
> hot fluid faster and in greater volume. Voila, Heat.
>
> It's very common. My 3.3 L chrysler V6 van blows cool at idle
> (172,000 kms) as does my Mazda 2.2 turbo (282,000 kms) when it's
> below -20 C. ( Which it is today)
>
>
>
> On 6-Jan-10, at 11:31 AM, mcneely4@cox.net wrote:
>
>> Someone else suggested the no heat when stopped situation is normal
>> during cold weather because the coolant temp drops. In my
>> experience, and that of a good many others, Vanagon usually runs
>> cooler when moving than when idling, due to increased air flow
>> through the radiator. But, if the water pump is moving fluid
>> poorly, perhaps the radiator and coolant pipes would have stagnant
>> coolant.
>>
>>
>> On Wed, Jan 6, 2010 at 12:13 PM, Don Spence wrote:
>>
>>> Tired water pump.
>>>
>>>
>>> On 6-Jan-10, at 8:38 AM, Automatic digest processor wrote:
>>>
>>>> No heat at stoplights.
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