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any experiences using Vacuum coolant purge and refiller?

Posted: Tue Jun 24, 2014 8:50 am
by langtoftnick
This coolant bleeding method seems so tortuous and complicated, and unlikely to have been used in the factory when the bongo was built, I was looking for alternatives.... like this....

http://www.amazon.co.uk/dp/B003BVD5NE/r ... aba2c9cbda

Does anyone have experience of using one of these on a Bongo? Does it do the job? Does it still need bleeding?

A bit pricey for occasional use I suppose but if it does the job properly it might be worth it.

Re: any experiences using Vacuum coolant purge and refiller?

Posted: Tue Jun 24, 2014 10:14 am
by dave_aber
I've got one.

It is most likely the system used in the factory - I can't see 3 people standing around every new Bongo with funnels, buckets, welding gloves, revving, shouting, topping up, etc for 1/2 an hour on each one!

So - does it work ? Yes.

I have refilled my coolant (well, the van's!) a few times, and have used this and the 'you tube video' method (solo, with my trusty 'accelerator plank')

When I have used it, I then tried a bleed - and got no more than the odd funnel full of fizzy stuff out.

However, it doesn't allow you to test the system through a complete warm-up cycle to the point where the stat is open and the fans are on. This is a good ting to do - as it gives you some confidence before driving off.

It also IMO could be a bit severe on a system with old crusty pipes. When you draw down the vacuum, the larger diameter pipes are crushed almost flat. Any which are a bit old & crusty may be weakened or fail - some would say this is asking for trouble, some would say it's a good test of their strength! My view is that it may cause damage on old pipes, and is stressing them in the opposite way to normal use (i.e. Expansion), so is posisbly abuse they don't need. If this shows up a weakness however, and I replace the offending pipe it may have been a good thing. Food for thought <discuss>

HTH

DA

Re: any experiences using Vacuum coolant purge and refiller?

Posted: Tue Jun 24, 2014 10:20 am
by langtoftnick
I was a bit worried about the tube flattening business, but as you say if the tubes can't stand up to that then maybe they should be replaced.. and I'd like to know in my driveway rather than on the A1. It also allows a test of air-tightness.

What is the approx cuft/min airline capacity needed to operate one of these effectively? I have a smallish compressor for my nail gun and tyre inflation etc, which has pretty good pressure but not a huge tank.

Re: any experiences using Vacuum coolant purge and refiller?

Posted: Tue Jun 24, 2014 10:39 am
by mikeWalsall
I have often wondered when people .. say print out the 'see saw' method and present it to the (even a Bongo savvy one) garage ..

Then @£50+ an hour if they actualy uses the method .. or the universialy accepted .. vacuum system, particuarly for mid engined cars like some Toyotas .. Mazdas .. MGs etc ..

A small (Aldi) nail gun compressor should be OK ..

Image

Re: any experiences using Vacuum coolant purge and refiller?

Posted: Tue Jun 24, 2014 11:46 am
by teenmal
You have less chance of damaging a hose with vacuum that you have with the normal coolant pressure.

With vacuum the hose collapses on itself (it then has self support)with pressure it does not have any support.

Just a bit of useless information.

Re: any experiences using Vacuum coolant purge and refiller?

Posted: Tue Jun 24, 2014 2:32 pm
by helen&tony
Hi
It's been discussed before about Vacuum fillers. They are perfectly O.K. with a good system, and often used on American Autos with BIG cooling systems...
Here's the catch....Almost without seeing other makes, I can assure you that Sealey, and all the major versions say they require 12 C.F.M. to draw a vacuum correctly...The 12 CFM is the ACTUAL air delivery rate needed, and NOT ....repeat NOT the quoted 12 CFM DISPLACEMENT that manufacturers quote in sales specifications for compressors ...for instance, a manufacturer quoting 12 CFM means that is likely to only deliver 8 or so CFM if you're lucky....Always look on the specifications for both figures...DISPLACEMENT and DELIVERY.
The next thing you need to look for is a compressor with a large air cylinder of a minimum of 2 or 3 hundred litres.
What you are looking for is, in essence, a workshop compressor, and something of well capable of delivering 12 cfm without tailing off. I had thought of getting one of those vac fillers and taking it to my local garage to get them to vac-fill, as my compressor is only a light workshop / heavy DIY type, and I don't want to lash out on anything as pricey as a fully plumbed workshop job!
If you ask at your local Bongo Garage if they have a vac fill, it might be worth a try, or buy one and take it with you to the workshop and ask to use their equipment with their help?....depending on how well you know them!
A small portable compressor is definitely not good enough to use, as the manufacturers clearly state 12 CFM DELIVERY...and using one may well fill the system, but most definitely will not purge the air and it clearly states in the instructions 12 CFM for that reason...Failure to read the instructions properly relating to the DELIVERY rate will require you to bleed the system. It'll fill but not purge!!!!!
Cheers
Helen

Re: any experiences using Vacuum coolant purge and refiller?

Posted: Tue Jun 24, 2014 3:18 pm
by helen&tony
Hi
Might I also add to the above post inasmuch as It's as Dave Aber says, YOU MUST really go through the heating cycle to ensure that the bottom hose gets hot, and the funnel method is one that rarely fails in terms of bleeding, whereas other methods have their place, the funnel method , when followed properly, has never been the cause of a disasterous bleed leading to head problems...It's tedious, and time-consuming, but it's reliable...
Cheers
Helen