Date:         Tue, 17 Sep 1996 22:42:36 -0500
Sender:       Vanagon Mailing List <vanagon@vanagon.com>
From:         Herb Harmison <herbh@iastate.edu>
Subject:      Changing Coolant '91 GL(Long)


A couple of months ago I changed the coolant in my '91 GL using some ideas
I picked up from this group. I improved a bit, I think, and would like to
pass on to those doing this job, what worked well for me.

The general idea is that the plumbing in the van is difficult to drain and
refill without doing a good deal of monkeying around. I don't like to work
too hard so I came up with the no-jack, no hose remove, no big mess method.

Basically what you do is to put fresh water into the expansion tank at the
rear and let it come out the radiator in the front. In order to do a good
flush you will need to run the car three or four times to get the old
coolant diluted and flushed out.

Here are the details that make the job pretty easy.

First, spend a few bucks on some plumbing stuff.

1. A 1 1/4" x 1 1/4" flexible connector. This is the thick rubber deal that
connects two pieces of poly pipe. It comes with hose clamps on both ends.
Cost $3.

2. A 1" female pvc to 3/4" mip pvc piece. This is a piece that a 1" pipe
will fit into with a 3/4" male pipe thread on the other end. Cost $1.

3. 3/4" female-3/4" hose adapter. This is a brass piece which goes on #2
and into which the end of a garden hose fits. Cost $4.40.

4. 3/8" FI x 3/8" fip. This is a small elbow deal made of brass. Cost $3.

5. 3 or 4 feet of 3/4" clear vinyl tubing. Cost $.50/foot.

6. Hose ends as needed. Cost $2 ea. After you read through this you will
have an idea of what you need.


1. Open up the engine cover and disconnect the braided hose that runs from
the expansion tank to the overflow tank. Carefully loosen the expansion
tank cap and remove. Some fluid may drip but not very much.

2. Take #2 and file off the letters on the outside of the molding. This
will make a better seal. Put #2 into #1 and tighten the clamp. Put #3 on #2
and screw a garden hose connected to an faucet into #3.

3. Put the assembly onto the cap threads on the expansion tank. This will
allow you to put water into the tank.

4. Take the front upper radiator grill off. There are 6 or 8 1/4 turn clips
that hold it on. It should fall out easily.

2. Take the out the plug that is on the upper right of the radiator. A
little liquid may come out.

3. Now you will have to do some fitting. Take #4 and see if you can gently
jam it between the bracket above the hole in the radiator and the hole.
Hopefully, there is some small amount of room. The room will provide space
for a soft rubber gasket that should be Super Glued onto the surface of #4.
I found that a bit of filing to make a tit above the opening in #4 makes
for a good pressure point. You are trying to get pressure on the gasket.

4. When you have the fitting so that it will stay pretty well, connect the
vinyl tube to #4 and support it so you don't get too much air in the
system. Actually, since the radiator is the highest point in the system,
you can bleed it as you finish.( There may be a good check valve but I
haven't found it.)

5. Turn the heater control to full open, hot.

6. Turn on the faucet gently and observe that there is a nice stream of
green liquid coming out of the radiator. Run fresh water until the stream
turns clear. I caught the coolant in milk bottles and disposed of it
properly. It took about 7 bottles for the clear water to appear the first
time.

7. You have now flushed the system a bit but not completely. Turn off the
water and quickly put the plug back in the radiator. Actually, if you can,
put the plug in while water is slowly flowing out to ensure there is no air
in the top of the radiator. Just don't create any pressures in the system.

8. Remove #1 from the expansion tank and put the cap and hose back on.
Front grill replacement is optional.

9. With the heater on, drive the car until the temperature is up to
operating temperature. At this temperature all the coolant is flowing and
mixing.

10. Repeat the flushing sequence until you are not getting much colored
liquid out of the radiator. You will then have the sytsem pretty clear. It
took me 3 runs.

11. To install the new anti-freeze connect up as above. This time you will
want to either pour the anti-freeze from a high point or gently pump it in.
I opted for pumping with one of the small plastic pumps driven by a 1/4"
drill. You may need to rig up a garden hose deal using the hose ends I
mentioned above.

12. With the drain hose at the front and two gallons of anti-freeze at the
back, you pump or pour them in. You will see a little change in color as
the second gallon finishes.

13. Be sure you have liquid coming out the radiator as you put the plug
back in to keep the nasty air out. Once you have done that, top off the
expansion tank and put any extra anti-freeze in the overflow tank.

13. Put the grill back on and you're done.

I found that two gallons of Sierra took me down to -29F which is OK.

Just to check out the cooling system we drove on vacation for 900 miles at
65 mph with a 1000# trailer, the A/C and four people in Iowa-Minnesota
summer. The van never even thought of overheating.

Good luck and I hope this saves a lot of work.

Herb Harmison
Ames, IA