Date: Thu, 21 Mar 2002 22:02:14 +0100
Reply-To: Robert Steven Fish <fish@SALZBURG.CO.AT>
Sender: Vanagon Mailing List <vanagon@gerry.vanagon.com>
From: Robert Steven Fish <fish@SALZBURG.CO.AT>
Subject: Re: self-bleeding coolant? LONG replay
Content-Type: text/plain; charset="iso-8859-1"
I don't get it...
why not just raise the front of the Vanagon?
Is that really so difficult to do? The basic principal of the air rising to
the higest point, make one think that even if you want to go though crazy
gyrations and manipulations to bleed the system... you should do them WITH
the front end raised.
Or am I missing something here??
RSF
<º)))>{ <º)))>{ <º)))>{ <º)))>{ <º)))>{ <º)))>{
Robert S. Fish
Salzburg, Austria
1987 Wolfsburg Vanagon 2.1 GL Weekender
1987 Golf Cabriolet
1991 Golf
----- Original Message -----
From: "Malcolm Stebbins" <Malcolm.Stebbins@MSVU.CA>
To: <vanagon@GERRY.VANAGON.COM>
Sent: Thursday, March 21, 2002 7:54 PM
Subject: Re: self-bleeding coolant? LONG replay
> On 20 Mar 2002 at 17:51, Dart 330 wrote:
>
> > How does one bleed the van without raising the front?
>
> I have done this several times:
>
> I flush - then drain the coolant system. To drain, I disconnect many of
the hoses. (I
> have even been known to BLOW HARD on some of the hoses to force any
> remaining liquid up and over any high spots to better drain the system).
>
> I then re-connect all of the coolant hoses, open the front and rear heater
levers,
> remove! the front radiator bleeder bolt, open the thermostat bleeder
screw-thingy on
> top of the thermostat housing (to let the air out for the next step).
>
> I look up the coolant capacity of the vanagon in the Bentley manual and
divide that
> number by 2 and use this quantity of undiluted coolant for the next step.
I begin
> adding 100% coolant into the rear-left coolant reservoir and maybe through
any
> convenient hoses that will fill the hoses going to the front of the van.
I fill as much as
> I can and maybe blow hard again to force the coolant up and over any high
spots
> (this is an oral adaptation/modification of the bicycle pump trick).
>
> Now I have my wife/son/friend watch the front radiator bleed hole, and I
watch the
> rear-left coolant expansion tank, and I start the van. I keep adding 100%
coolant till I
> run out (of the numbers of litres that I know make up a 50/50 mix). After
I run out of
> coolant, I switch to adding water (take your pick between distilled and
tap water).
> The thermostat bleeder screw-thingy will start to squirt soon and when it
does, I
> close it.
>
> When the coolant starts squirting out of the front radiator bleeder hole,
(I may need to
> wait for the van to warm up and I may have to rev the van a bit for this
step (that's
> where the 2000 rpms comes in that we hear about)) I turn off the engine
and screw in
> the front radiator bleeder bold - hand tight!
>
> All the while, I keep an eye on the coolant level in the rear-left
expansion tank,
> adding coolant (or then water) as needed to keep it full and feeding the
water pump -
> don't want the water/coolant pump to go dry with the engine running.
(Some people
> talk of an air locked water/coolant pump, but I have never had this
problem).
>
> If things are going smoothly, the system will stop taking water in the
rear-left coolant
> expansion tank. I then loosen the front radiator bleed bolt and let the
air out while
> reving the engine, then when coolant comes out, I hand tighten the front
radiator
> bleeder bolt. Now I repeat the sequence: rev, bleed, add coolant, rev,
bleed, add
> coolant, rev, bleed, add coolant, for a few minutes.
>
> By now the engine as been running for 10 or 15 minutes and the temp gauge
needle
> on the dash has started to rise and then I know that the thermostat has
opened. This
> helps move more coolant and air around the system to either the front
radiator or to
> the rear-left expansion tank. Repeat the front radiator bleed.
>
> Pretty soon things calm down and I get no more air out of the front
radiator and I can
> add no more water (water by now) to the rear-left coolant expansion tank.
I tighten
> the front radiator bleeder bolt. Put the cap on the rear-left coolant
expansion tank
> and connect the hose to the rear-right overflow tank (behind the licence
plate). I may
> try and bleed the rear heater with the bleeder screw that's on top of the
on-off valve.
>
> Now I am pretty sure that MOST of the system is filled with coolant and I
have MOST
> of the air out of the system. I may still have some air in the system,
but I can drive
> the van.
>
> I fill the rear-RIGHT overflow tank with a 50/50 coolant mix up to about
1/2 to 2/3 of
> the tank. I can now either drive the van or I can turn it off, and when
the coolant
> does (eventually) cool down, coolant will be sucked from the right
overflow tank into
> the left expansion tank (this is my vocabulary anyway).
>
> Now I can drive the van and I do. I leave the front grill off so that I
can quickly and
> easily bleed the front radiator about every 100 kms (when the engine is
warmed up
> and at 2000 rpms). The act of driving the van atomizes any air into small
bubbles
> and passes it along (usually) to the front radiator or the rear-left
coolant expansion
> tank. After about 3 or 4 times (300 to 400 kms) of bleeding the front
radiator, the
> thermostat housing pee hole, and filling the rear left expansion & rear
right overflow
> tanks, I get no more air out of the system, I am pretty sure that nearly
all of the air is
> out of the system.
>
> I should say that I have a Canadian spec 1991 syncro (westy) which has
(after the
> PO's engine-box fire) a bastardized coolant hose system (and a carb) so I
may have
> easier access to some of the hoses than you FI guys.
>
> So that's how I bleed my van's coolant system without raising the front
end. Of
> course it helps if you live in a hilly part of the country, that way
driving up a steep hill
> will help move the air around.
>
> On this list I have read of several methods of bleeding the coolant system
and I only
> put this procedure forward as 'a' method and not as 'the' method and maybe
it should
> only be used in emergencies or when driving through the Egyptian desert
and your
> coolant system blows and you need to get home ASAP.
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