I have some pics of the city water mod when I took the port out of my '82 westy. 

http://shufti.wordpress.com/2010/08/10/westy-city-water-port-fan-mod/

I cut a square of closed cell foam which fits in the port tightly and acts both as a gasket when flap is down, and as a prop when flap is open and fan running. I never used it while driving.

alistair

On 2011-09-25, at 3:37 PM, Edward Maglott wrote:

> Thanks everybody for the great info!  Especially the photo set linked
> below.  I somehow missed that one before.
> 
> How do you guys handle the little door on the city water fan
> setup?  It sounds like you run it even while driving?
> 
> Phil says:
>> The material for this was sourced at a FLAPS. Aluminized ceramic
>> cloth with a velcro
>> zipper. Cut to length and wrap around bare Al exhaust pipe.
> 
> I want to look at that product at the FLAPS, what purpose is it sold
> for?  I thought about the exhaust wrap tape but worry it might not be
> good for indoors given the previous warnings about some insulation
> causing a smell there.
> 
> Running my fridge outside the van I was impressed at the amount of
> air convecting straight up the back.  Works great with unlimited free
> air available...
> 
> Edward