TheSamba.com :: View topic - Coolant Bleeding the No Stress, No Mess Way!

Sun Oct 09, 2022 4:32 pm

MayorMcCheese,
Very clever of you to create this and overly kind to share the files for it!

Much praise to you!

Dave

Thu Nov 17, 2022 5:35 pm

MayorMcCheese wrote: I was tired of trying to get the rubber coupler to seal on the threads of the coolant tank so I deigned and 3d printed this. It threads on uses the rubber washer out of a spare coolant cap to seal.

For future reference the threads of the coolant tank are M48x3

More info and print files here https://www.thingiverse.com/thing:5556688

You're the man! Incredible work! I found this on Thingiverse and came to this thread to give you praise. Awesome modeling skills!!

I can't imagine a better Libby bong.

Fri Nov 18, 2022 11:08 am

Very cool nice work. Imagine a bicycle pump attached to the other end of that cylinder. How about a glue on cap assembly with a reinforced hole in the end for a plunger/ piston with an o ring. You could force the coolant through.

Fri Nov 18, 2022 2:53 pm

That's a dope design. Well done, and thanks for sharing!

Thu Sep 21, 2023 12:18 pm

I had to replace my water pump recently and thought to build one of these bongs to bleed the cooling system. However since I already had a pump up garden sprayer for bleeding brakes, I thought I’d try that first. Filled the reservoir up with coolant, put the cap on and pushed the sprayer hose on to the overflow nipple. Opened the bleeder screw at the top of the radiator and gave the sprayer several pumps. The coolant level dropped a bit so added more coolant and re-pressurized. Walked around to the front of the van and checked the bleeder. A few seconds later coolant began to spring forth. Closed the bleeder screw and removed the sprayer. Topped off the coolant and fired up the engine. Done. Worked super slick. Highly recommend this method.

Thu Sep 21, 2023 2:49 pm

MI-Bug wrote: I had to replace my water pump recently and thought to build one of these bongs to bleed the cooling system. However ...

That's basically what I do too.

I tried the Libby Bong but whateve rubber boot I had didn't seal well and made a big mess. I bought the GoWesty "pump thing" which is really just a Schraeder valve stem and low pressure hand-pump and it works great.

I can't believe how ellaborate the VW factory method is when there are such easier ways to go.

Fri Sep 22, 2023 11:00 am

Maybe I have not read the thread deeply enough or maybe this belongs in the Stupid Questions thread, but...

Has anyone Libby Bonged a GoWesty aluminum tank?

Fri Sep 22, 2023 2:59 pm

Jim Bear wrote: Maybe I have not read the thread deeply enough or maybe this belongs in the Stupid Questions thread, but...

Has anyone Libby Bonged a GoWesty aluminum tank?

Yeah.
I have a big funnel with a spout that fits into the neck perfectly. I just push into the neck and it seals up great.

Tue Sep 03, 2024 10:21 am

Is there any reason to NOT just start with filling coolant at the radiator bleed screw end? granted it's a pretty small opening (slow) but seems to me that you could get a ton of coolant in without running the engine and/or repeatedly topping off the coolant tank & pressurizing. Or is that not going to be a time/effort saver?

(needing to do a coolant refill after replacing the water pump.)

Tue Sep 03, 2024 10:44 am

jjdeluxe wrote: Is there any reason to NOT just start with filling coolant at the radiator bleed screw end? granted it's a pretty small opening (slow) but seems to me that you could get a ton of coolant in without running the engine and/or repeatedly topping off the coolant tank & pressurizing. Or is that not going to be a time/effort saver?

(needing to do a coolant refill after replacing the water pump.)

Interesting idea. I'd wonder too... You might be the trial subject :)

The banjo bolt on the vanistan heater shut off/bleed tube is already there for those that have it.

Tue Sep 03, 2024 11:09 am

vanis13 wrote: jjdeluxe wrote: Is there any reason to NOT just start with filling coolant at the radiator bleed screw end? granted it's a pretty small opening (slow) but seems to me that you could get a ton of coolant in without running the engine and/or repeatedly topping off the coolant tank & pressurizing. Or is that not going to be a time/effort saver?

(needing to do a coolant refill after replacing the water pump.)

Interesting idea. I'd wonder too... You might be the trial subject :)
.

No one has time to be the trial subject on this job.

There's no reason not to do it that way as long as you're patient. The "inlet" to the radiator is what, a few millimeters in diameter? It would take a loooooong time to fill through that hole and there's also a sharp bend to navigate (kink your hose) with whatever tiny hose you're using due to the overhang of the body work at the top of the grill.

Topping off the coolant at the expansion tank and pressurizing with a bicycle pump for a few cycles takes about 5 minutes and doesn't result in any mess except a tiny bit of coolant that might run out of the radiator bleed screw.

Tue Sep 03, 2024 11:16 am

Buying a banjo bolt & tubing for this project is not a big cost or effort.

But you gotta hook up the tubing to fill somehow, rig a filler reservoir.
Cuz it’s gonna go in slowly.
Also are you leaving the reservoir (rear) open?
Then you have to watch it fill (slowly) & cap it the moment its full.

If you just let it fill from the radiator without capping at the right time, higher level flows out of the reservoir and the “radiator air level” ends up the same as the basic method.
OK you wouldn’t do that, you would sit at the reservoir watching like a hawk, waiting for it to rise, capping at the right time.
I guess you’d have to try it and see of its efficient. .

Coolant coming in very slowly might just flow in “under the air” and still end up with a lot of air behind the banjo and in high spots in the system. And trapped in the radiator. Will the trapped radiator air come out by gravity up through the banjo tube that coolant comes into? Maybe.

Theres a simple straight rubber pipe that fits tightly into the rear reservoir that will fill much easier (the classical “Libby Bong”) where just the air comes out of the rad bleeder. This is probably faster than coolant going into the banjo by gravity. Its easy pouring into the bong, directly into the reservoir. It fills the long coolant pipes quickly too.

I hated coolant bleeding before learning two vastly better methods.
I’ve done the gravity ass-end-up (Libby Bongless) method and the level Libby Bong method
and can’t really imagine how any other method could be easier.
Just fill it, bleed front, run it, bleed front, done - super simple.

Anyway filling from the front is a feasible suggestion that would be easy to test!

Tue Sep 03, 2024 11:24 am

I modified my method the other day, since I wanted to pressure test it anyway.

And… we carry nothing we don’t routinely use, or need.

Pumped to 14, waited a half-hour to test, opened rad bleeder until coolant ran solid, closed bleeder, removed tester, topped off.

Two tasks done in one.

Tue Sep 03, 2024 11:44 am

Thanks all for your input and particularly SCM for answering my question and offering sanity as well. I have something like this - I'm sure I can pull something off (pressurize and fluid fill at the same time!?)

I have massive mess already - that ship has sailed. removing the water pump just spills coolant all over the under carriage and deflects everywhere. Next time I'm getting a 4' diameter kiddie pool to capture everything.

SCM wrote: There's no reason not to do it that way as long as you're patient. The "inlet" to the radiator is what, a few millimeters in diameter? It would take a loooooong time to fill through that hole and there's also a sharp bend to navigate (kink your hose) with whatever tiny hose you're using due to the overhang of the body work at the top of the grill.

Topping off the coolant at the expansion tank and pressurizing with a bicycle pump for a few cycles takes about 5 minutes and doesn't result in any mess except a tiny bit of coolant that might run out of the radiator bleed screw.

Tue Sep 03, 2024 11:54 am

I personally don’t see any advantage filling at the radiator, but rather unnecessary thread wear avoided if filling from the tank — and letting minor leftover air self bleed (which it does, but over time).

I only tapped ours yesterday while dead-cold, in knowing we’re getting a few bubbles into the tank and trying to eliminate “head gasket leak” as a possibility.