View original topic: Coolant Bleeding the No Stress, No Mess Way! Page: 1, 2, 3, 4, 5, 6, 7, 8, 9  Next
?Waldo? Mon May 28, 2007 12:04 pm

I've had a thought for a little while now and finally got to try it out. I've needed to do a little cooling system work so drained and refilled. I've gotten quite good at the stock method of bleeding the van, but it is always a little stressful and messy even when you have the procedure down pat.

Here's what I rigged up:

It consists of a piece of ABS, a PlumbQuick connector, a short section of nylon hose and a rubber band. All three parts are readily available at any hardware store for cheap. The connector has to be the correct size to fit over the top of the coolant bottle and over the section of ABS. The ABS tube needs to be long enough to extend from the top of the expansion tank to a few inches above the top of the radiator. You install the connector on the abs and then drill a hole just above the top of the connector. The hole needs to be a little smaller than the outer diameter of the nylon hose. I would recommend 1/2" O.D hose. I used a smaller diameter only because it is what I had lying around. The nylon hose then gets pushed into the hole you drilled and pulled through until it extends below the bottom of the coupler.When it is time to fill the coolant system, you remove the cap from the expansion tank and fit the coupler on making sure the nylon tube extends into the coolant tank opening. The other end of the nylon hose is in place near the top of the ABS. With the two clamps on the coupler tight, the tube then gets filled with coolant until the coolant level is above the top of the radiator. You then open the bleeder valve on the radiator and listen until the air stops rushing out or until coolant starts to flow out. If the air stops and coolant has not yet flowed out, you close the valve and add more coolant to the ABS tube and have another go. Once the coolant flows out of the radiator, you close the bleed valve and start the van. You can rotate between adding coolant to the ABS tube, briefly opening the radiator bleed valve and revving the engine. Once it is up to normal operating temp, has been revved a few times and the air is out of the radiator, shut her down. You might wait for the van to cool down or wear gloves for the next bit. While holding the nylon tube, undo the rubber band. slowly lower the tube until coolant is very close to the end of the hose. Pinch the hose and stick the end in your leftover coolant jug with it sitting below the expansion tank. Relase the nylon hose. This will start a siphon going which will drain the coolant out of the ABS tube and connector. You can then undo the connector and top off the expansion tank and burp tank and put all the stuff away for next time.

It works GREAT! No more mess, no more stress.

EDIT 7/17/14:

The Libby Bong 10-Step Program

1. With the engine off, turn heater to hot and open the rear heater valve.

2. Install the bong on the pressure tank and fill it almost full.

3. Open bleeder on radiator. If coolant comes out of bleeder then close the bleeder on the radiator and proceed to step 5. If coolant does not come out of the bleeder then close the bleeder and proceed to step 4.

4. Top off the level in bong and go back to step 3.

5. Start engine and rev it up for 2 seconds and then shut it off.

6. Top off bong and open bleeder on radiator. If coolant comes out of bleeder then close the bleeder on the radiator and proceed to step 7. If coolant does not come out of the bleeder then close the bleeder and proceed to step 4.

7. Drain bong and replace the cap on the pressure tank. Top off burp tank at license plate.

8. Drive the van around until it is warmed up a bit.

9. Stop somewhere that the passenger side is slightly higher than the driver's side and open the radiator bleeder. If coolant leaks out then proceed to step 10. If only air hisses out, then re-read the process and make sure you followed the instructions exactly. If you see that you did not follow the instructions exactly then start over at step 1. If you see you did follow all the instructions exactly then proceed to step 8.

10. Park the van and allow it to cool off. When cool, top of pressure tank and burp tank. Look at and top off the burp tank every day or so until the level when cold is consistent.

You may notice that the updated instructions do *not* include running the engine with bong in place until warm.


?Waldo? Mon May 28, 2007 12:08 pm

The van in the pictures has a 2.0L ABA inline-4 with the 8 valve CIS-E head fitted. The procedure would be the same for a WBX or diesel motor.

The distinct advantage to this as a system is that it raises the coolant level at the expansion tank above that at the bleeder and so allows gravity to push all of the air out of the radiator. No more high revving while trying to pour coolant into the expansion tank. No more geysers at the bleeder valve. No more dead cats in the neighborhood (at least from the coolant spills).


tencentlife Mon May 28, 2007 2:47 pm


I was wondering when I first saw the picture how you would deal with the fluid left in the pipe column. I was thinking it should have a valve at the bottom, but it soon became apparent what you had in mind. Excellent! Simple, cheap, effective, all the stuff I love.

?Waldo? Mon May 28, 2007 3:14 pm

Thanks, I'm quite proud of the design.

I thought of one more great use. You can stash it under the rear seat for use as a conversation piece in the event that authorities search your vehicle. :lol:


tencentlife Mon May 28, 2007 3:16 pm

That's not a conversation I'm eager to have.....

riceye Tue May 29, 2007 6:20 am

What a beautiful thing, Andrew. I nominate for a stickie!


backcountrymedic Tue May 29, 2007 6:52 am

Oooh! It could double as a potato gun! Nice friggin' work!

TSR53 Tue May 29, 2007 8:46 am

This is a FANTASTIC solution! I used to own several Porsche 944's and they were a cranky SOB to get bled properly. Once done, it was bliss free. It's the process [right before it get's too hot, etc] of reving, filling burping. Just like a baby...


I've always used the Audi/VW blue coolant [G12 right?] for my '95 //S6, just curious what I should be running in my new-to-me wasser boxer?

TSR53 Tue May 29, 2007 10:32 am

Well, looking through my records it shows "G12" coolant refill back in 2003 !!! Eecks!! I topped off the overflow tank with G11 - drats. Should never mix the two Audi blue (G11) with newer pink or purple G12... not knowing what color was in there, I topped it off right before my trip home with what I had on the shelf. Everything runs within spec and seems to run cool.

Hmmm, looks like I'll have to get the coolant flushed asap prior to my summer vacation.

I'm going to buy the parts for this coolant apperatus this afternoon!


1. Should this be done with the radiator or front end raised?
2. This is done cold correct, and both front and rear heater valve open?

Thanks Andrew!

?Waldo? Tue May 29, 2007 12:25 pm

No need to raise the van, although it might help move some bubbles this way or that. As mentioned in the initial description, I would add the aparatus and fill it cold and bleed what you can that way, but run it until the thermostat opens while periodically revving it, opening the bleeder and topping off the coolant level. I would certainly have the heater valves open.


kayakwesty Tue May 29, 2007 1:39 pm

I ....2nd for a Sticky!!!!

psych-illogical Wed May 30, 2007 3:10 pm

Andrew A. Libby wrote: No more dead cats in the neighborhood (at least from the coolant spills).


Take all the fun out of it why don't you :wink: .

BTW, 'nuther vote for a 'sticky.' This is just too cool.

buschy Sun Jun 24, 2007 7:36 pm

Thank you Andrew Libby! I hate to admit this, but I've had my '84 Vanagon high top parked at the back of my yard for almost 6 years, because I was dreading the hassle of replacing the leaky radiator. I knew the worst part of the job would be bleeding the system, and quite frankly, I was clueless. Then, I stumbled across this forum. I went to my local home improvement store today, and bought the necessary parts. It took me a couple of hours to get the old, rusty, leaky radiator out, and the "new" one in (I bought it off a totaled Vanagon 6 years ago, and seems fine so far). I used the Libby pipe method to bleed the system, and took the kids for a cruise tonight! I wouldn't have been able to do it without this post, so a most sincere thank you is due. Another vanagon again on the road! Maybe I'll take the family camping this weekend. hmmm...

:D :D :D :D :D :D :D :D

funagon Sun Jun 24, 2007 9:43 pm

I've read your description twice. Correct me if I'm wrong, but I think I've achieved the same effect by jacking up the rear of the van until coolant resevior is at least as high as the radiator bleed bolt. This is how I've always filled with coolant. I keep all heaters set to hot, radiator bleed open, rear heater bleed open, thermo bleed screw removed. Then I fill the resevoir until coolant comes from the rad and plug it, then keep filling till coolant comes from the rear heat valve and plug it, ditto on the thermostat bleed screw. Finish filling, lower van, and drive. I've done this without bleeding (no revving at 2k RPM, etc) and it works fine for me. On my first drive I stop and refill a little if the level goes down.

Terry Kay Mon Jun 25, 2007 10:29 pm

While this gizmo looks like a good idea, The way I get it done is a little bit less complicated and direct drive.

I fill both the expansion, and the reservoir tanks, and attach my Snap On pressure tester.

Pump her up to 15 lbs, and open the radiator bleeder.

Maybe at the most I have to pump the up pressure twice.

The air is forced out through the top of the radiator, and it takes all of 10 minutes.

The biggest advantage of having the pressure tester in stock, is I can also pressure test any Vanagon coolant system ( or any coolant system) for leaks in a hurry.

The potato cannon tube is only good for bleeding the system.

Good idea, but limited.

Kinda reminds me of a bong ---

uther Fri Jul 20, 2007 6:44 pm

Terry Kay wrote: While this gizmo looks like a good idea, The way I get it done is a little bit less complicated and direct drive.

I fill both the expansion, and the reservoir tanks, and attach my Snap On pressure tester.

what's the model number of your snap on pressure tester? i'm thinking of buyone one off ebay but i want to be sure it will work on a syncro.


Terry Kay Fri Jul 20, 2007 8:40 pm

I'll have to take a look at the pressure tester kit tomorrow while I'm at work, and give you the number off of the box tomorrow night.

It really isn't just the kit you'll need.
Your going have to purchase the VW expansion tank screw on adaptor along with it too, to make it fit the Vanagon.

Terry Kay Fri Jul 20, 2007 10:34 pm

The Snappy coolant system tester's part number is;

The adaptor specificly for the expansion tank is TA16B.

I'll double check on the part number for the expansion tank screw on adaptor tomorrow--but the presuure testing equipment I have is the number that I posted above for sure.

BTW, the tester isn't just idiginous for a Syncro.

It'll work on all water cooled Vanagons.

BoneStock67 Sat Jan 26, 2008 4:07 pm

Well, I just bought the parts for Andrew's elegant approach, if only because it seems so darn cool.
I was a bit confused at first about PlumbQuick, because when I searched on that term, all I got was a plumber in New Zealand.
But when I got to Home Depot, all became clear: it's spelled PlumbQwik.
I bought a section of 2" diameter PVC and a 2" to 1.5" PlumbQwik reducer, which fits very nicely right over the expansion bottle opening.
As soon as I get the replacements for my leaky hoses, I'm going to fill and bleed with my new toy.
Thanks, Andrew!

reiney Sat Jan 26, 2008 5:45 pm

Nice job Andrew! That's a great piece of engineering ...

Powered by phpBB © 2001, 2005 phpBB Group