Date: Fri, 12 Jan 2007 03:33:49 -0500
Reply-To: Bill Glenn <idahobill@GMAIL.COM>
Sender: Vanagon Mailing List <vanagon@gerry.vanagon.com>
From: Bill Glenn <idahobill@GMAIL.COM>
Subject: Re: radiator bleeding valve
Bleeding the air at the top of the radiator is easily done by loosening the
bleeder bolt. The problem occurs when the air has been purged, followed by
coolant coming out at the bleeder bolt, but you're not there to see it
because you're at the back of the van replacing the coolant in the
expansion tank as it's taken up by the water pump to fill the system. The
result is coolant down the front of the van and on the ground. Caught in
time, outdoors in summer, the clean-up is easily done with water from the
hose (though I don't want excess toxic coolant hosed into the gutter).
Outdoors in winter where I live, spraying water is a poor option, because
it will ice the driveway for weeks. Indoors in the garage, I don't want
coolant pouring on the floor and splashing around either, because a water
clean-up is not an option (too much stuff around).
This has been my solution: Use an 8mm bolt with the same thread as the
bleeder bolt on the radiator, 25mm long having a full thread, (normally a
13mm head if of euro origin). Place the bolt in a drill press vice, head
up, making sure the bolt is perfectly plumb when clamped in the vice.
Center punch the exact center of the head, then drill a 5/32" hole down
through the head, continuing all the way through the length of the bolt.
Remove the bolt from the drill press vice, and place it in the machinist's
vice, gripping it by the head. Using a hacksaw, cut the head off the bolt
and discard the head. Lightly dress the cut end of the bolt shank with a
file to de-burr it. Slip a 30" piece of very flexible 5/16" i.d. rubber
hose over half the length of the bolt threads, starting from the cut end.
(the flexible rubber is easier to work with when screwing the bolt into the
radiator than vinyl hose would be). A clamp on the hose is not needed.
When replacing the coolant in the Vanagon, temporarily remove the radiator
bleed bolt, and replace it with above bolt/rubber hose. Screw it in just
until the rubber hose makes contact with the radiator. Let the hose dangle
into a clean five gallon bucket or drain pan. Fill the expansion tank with
coolant and start the engine. Now just stand at the back of the van and
pour more coolant into the expansion tank as needed, increasing the revs on
the motor to force the coolant through the system and up into the
radiator. No need to concern yourself about coolant coming out the
radiator, because it's being fully captured in the bucket. Allowing
coolant to exit the top of the radiator in this manner for several minutes
seems to purge much more air than when the bleeder bolt is closed down at
the first sign of coolant coming out. When done, the captured coolant in
the bucket is poured back into one of the original coolant bottles and
carried in the van and used to top off the expansion and overflow tanks if
needed. After one trip of moderate distance, the remainder of the air is
usually purged, and the coolant level stable, only needing to be topped off
to the desired level. The bolt/hose combination, which cost less than a
dollar and fifteen minutes of my time, is rolled up and stored until next
time.
|