Small ones do it just like we do if they understand the Vanagon cooling
system, and big ones that have flushing machines simply hook it up and flush
new coolant through displacing the old.  Some also use a cleaner first, and
of course they must have the proper coolant in the machine.  They then
recycle the old stuff.

Stuart

-----Original Message-----
From: Vanagon Mailing List [mailto:vanagon@gerry.vanagon.com] On Behalf Of
Rocket J Squirrel
Sent: Friday, May 11, 2012 8:06 AM
To: vanagon@GERRY.VANAGON.COM
Subject: Re: Let's Talk Coolant Drainage (long)

So I wonder how a shop flushes the system before putting in new coolant.
Do they also reckon that they'll only get half of the old coolant out and
just dump new in atop the old stuff?

The cooling system is a marvel of spaghetti engineering. I'd like to see a
3D model of the thing. As many times as I've looked at the hoses, I still
don't have a good sense of all the roller-coaster highs and lows in the
thing.

Even with a tee in the heater hose, which has to be the lowest spot in the
system, so much coolant stays behind. It must be pooled in low spots that
have higher entries and exits.

--
Jack "Rocket j Squirrel" Elliott
Bend, Ore.
1984 Westfalia. A poor but proud people.
1971 "Ladybug"-brand utility trailer ca. 1972 from a defunct company in San
Clemente, Calif., now repurposed as The Westrailia.

On 05/10/2012 08:55 PM, Alistair Bell wrote:
> I understand and sympathize. I had difficulty getting it all out, even
using a shop vac (with intermediate 20 l bucket). But I do think I got more
out with the shop vac than when I did it without.
>
> alistair
>
> On 2012-05-10, at 8:15 PM, Rocket J Squirrel wrote:
>
>>
>> Clearly, I never drained anywhere near most of the old coolant.
>>
>> I am puzzled. Oh -- the heater valve was open.
>