Date: Sat, 12 Jan 2008 23:29:49 -0500
Reply-To: Dennis Haynes <d23haynes57@HOTMAIL.COM>
Sender: Vanagon Mailing List <vanagon@gerry.vanagon.com>
From: Dennis Haynes <d23haynes57@HOTMAIL.COM>
Subject: Re: Coolant flow/air bleeding
In-Reply-To: <003201c8556a$b89e5e20$7427e804@g4rjd6533y07g0i>
Content-Type: text/plain; charset="iso-8859-1"
One thing to consider is that once you made the decision to drive the van
home after the cooling system failed, you really made the decision to
replace or at least do some repair to the engine. If there was some chance
of escaping damage from the first trauma you chose to continue to damage
things anyway. I have posted many times on the proper way to bled the
cooling system so here it is again.
For starters, after any over heat steam event, the pressure cap and
thermostat should be replaced.
No need to raise the front. In fact that makes it more difficult for the
pump to get the coolant up there.
Since it is winter, consider pre mixing the coolant and water. Just in
case you don’t get the vans running long enough to really mix it.
You want to do this with a cold to cool engine.
Fill main pressure bottle, allow time for as much as possible to flow into
the engine. Open the t-stat bypass and both heater valves.
Start the engine and either with a smartly placed screwdriver holding the
throttle or a friend at the gas pedal, get a fast idle, 1,500 2,000 rpm.
Keep the main pressure bottle full. Slowly open radiator bleed. You should
hear some air escaping until coolant flows out. When stream is fairly
steady close bleeder. Top off main or pressure tank and replace pressure
cap. Allow engine to return to normal idle speed. Close bypass, reconnect
hose from cap to overflow. Top off overflow and you are done.
This should be done on 5 minutes or so. Let engine run and feel for
coolant flow to radiator. Idle long enough to test fan operation. If all
is good any small amount of air will work its way out in a few heat-cool
cycles. Check the overflow for a few days as some coolant will get sucked
in. If you see regular bubbling in the overflow tank than failed internal
head gaskets or cracked-loose heads are the likely cause.
Dennis
-----Original Message-----
From: Vanagon Mailing List [mailto:vanagon@gerry.vanagon.com] On Behalf Of
mike stainbrook
Sent: Saturday, January 12, 2008 5:30 PM
To: vanagon@GERRY.VANAGON.COM
Subject: Coolant flow/air bleeding
I have an 85 7 pass,manual trans that has air bubble problem-the line from
fill bottle to resivor worked loose,chopped by fan belt,overheated,I eased
it home,replaced the line,put front end up on ramps,filled resivor and
refill,ran with rpm@2K,heater on,bled from Kennedy valve on radiator,kept
resivor full,got steady flow at first,then as engine heated up,flow
stopped.-still have overheat problem,did get some hot coolant out of bleed
valve.should I assume it's the thermostst sticking? in theory,by closing
resivor and refilling via fill tank,should be able to"recycle" all
coolant.(or,I'm way off base) need input on solution to overheat problem.
Thanks everyone, Mike
mike90260@yahoo.com
|