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Coolant -how do Mazda replace it

Posted: Sat Nov 24, 2007 11:23 pm
by bournemouthken
I've read the factsheet on replacing the coolant and to be honest, it sounds pretty long winded to me, how on earth do Mazda cope when on the assembly line, with Bongo's flying out of the factory at a rate of knots, they must have a fast and foolproof method of filling up from new, I can't see the workers over there using a long winded method which takes a lot of time,
Any ideas???

Posted: Sat Nov 24, 2007 11:28 pm
by Dave up north
Dont know... But you have got a good point there.
Come on techys... Get your grey matter round this one then.

Posted: Sat Nov 24, 2007 11:30 pm
by scanner
Apparently there is special stuff in the engine when it's installed - all they have to do later is just add water to taste.

Posted: Sun Nov 25, 2007 12:02 am
by MattK
My clanky says he has a vacuum bleed thingy.
He reckons using this to bleed the coolant system would eliminate any airlocks and avoid all the malarky in the fact sheet.

should i believe him?

coolant change

Posted: Sun Nov 25, 2007 7:57 am
by helen&tony
Hi
There are a number of models of vacuum purge/ replenish systems on the market from around£60.00 upwards. Your mechanic probably has one. They are driven from a compressor. When I get my silicon hoses, I shall probably invest in one....small price to pay for peace of mind and no airlocks....along with one of Haydn's magic gauges and an engine temperature sensor!!!!!....I must be paranoic
Cheers
Helen

Posted: Sun Nov 25, 2007 10:41 am
by nfn
I'm considering getting a vacuum refill system -- which will refill the cooling system in minutes without the need for bleeding air using the seesaw method or other means. I was almost ready to buy the Sealey VS0041, and was looking at what specs the compressor needs to have to run it. It does not need especially high PSI, but the specifications state the Sealey's air consumption is 12CFM. This is a lot of air! It would require a big compressor (£1000 or more). Most compressors can put out about 6CFM. I e-mailed Sealey tech help about this, but got no reply. At the same time, I looked into the US equivalent (the Mityvac). Their tech help said that you can run the Mityvac okay with 6CFM, although it was designed with use of a powerful shop/garage compressor in mind. So now I'm leaning towards getting the Mityvac...

Has anybody on the forum used the sealey? and if so, what compressor do they have?

coolant change

Posted: Sun Nov 25, 2007 1:46 pm
by helen&tony
Hi Nfn
You can get a 12cfm compressor for less than a grand these days, or look at a second hand one in good nick....you can even build one up from component parts. Regarding the purge/ refill systems, P.M. me and i'll give you more details. If you do go and get a compressor, consider all the air tools you can run....they are cheaper than electric tools, as you dont have a motor to include in the price. We gave a whole lot of air ratchets, and so on away, as we don't do much rebuilding these days, but the compressor stays. I havebought Sealey stuff, but not the purge/ refill.
Cheers
Helen

Posted: Sun Nov 25, 2007 3:47 pm
by bigdaddycain
You haven't heard this from me, but , a well known importer has suggested that the textbook method of coolant changing,(and subsequent bleeding procedure) had more to do with putting people off attempting to bleed the systems themselves,and instead, paying mazda dealers in japan the equivalent of £100 to do the job... Subtle hints of invalidating warranties was enough to make people cough up.

Then the dealers would bleed the sytem anyway they felt adequate...(usually the fastest method)

Like i say...you didn't hear this from me :lol:

Posted: Sun Nov 25, 2007 3:54 pm
by nfn
Thanks Helen. Do you know what it means, practically speaking, to have a lower air flow compressor? My guess is that if you are using a coolant refill device, you will be standing there happily creating a vacuum in your cooling system when suddenly you will have a pause in air delivery from the compressor. The compressor will then kick back in when it's ready. This should not really matter. However -- I could be wrong about how a compressor works, only having used one a couple of times...

Also, I assume that refill systems such as the Sealey were designed to be used on all vehicles, from tiny ones all the way up to 18 wheelers. The size of the cooling system will determine how much sucking has to be done to create a vacuum in the system. Maybe 12cfm is what it takes to suck out the cooling system of a London bus. The Bongo system will be much smaller, and hence not need 12cfm of air to pull a vacuum.

Posted: Sun Nov 25, 2007 5:58 pm
by tonygadget
Hi NFN,
I have a compressor thats more than beefy enough for 12cfm

if you do go ahead & buy the sealy your welcome to come & use some Essex air!

I think they use the high flow rate to create the vacuum in the same way that a parafin cleaning gun/grit blaster etc works. ie point & blow vast quantities of air down the straight bit of a "t" pipe. the resulting rush of air creates a vacuum in the "t" bit.

I think the main problem with using a 6cfm compressor would be when the air receiver runs out & the compressor restarts then you will lose compression (& perhaps cause an airlock)

Using a bubbler (large unsquishable container with small amount of water in bottom & inlet pipe under the water) attached to a vacuum source (the Bongo has a few when running) you might be able to make up one on the cheap as long as two Bongos can get together (1 for vacuum other being filled).

Posted: Sun Nov 25, 2007 6:07 pm
by MountainGoat
Bollocks, to think that I used to live in Brentwood just down the road from you until four years ago. Now I am miles away. :( But then my sister still lives in Brentwood so you never know when I will come knocking at your door.

coolant change

Posted: Sun Nov 25, 2007 7:14 pm
by helen&tony
Hi Nfn
The answer is that if you use a compressor with a lower delivery in terms of air output ,it just won't work, and ,maybe , you will get an airlock as the machine won't work properly....the air requirements are quite specific...think of it in terms of voltage......a 240 volt appliance won't work off 12 volts....as I say, P.M. me and I'll go into your enquiry at length, without boring the masses....you know it makes sense...buy a compressor and work well with mechanical assistance!!!!!
Cheers
Helen

Coolant-

Posted: Mon Nov 26, 2007 1:27 am
by bournemouthken
Blimey, from what I've read on here, am I right in saying then that if you put a vacume onto the air bleed hose under the passengers seat, and keep topping up the expansion tank, then you will fill up the cooling system eventually without creating air locks?

coolant change

Posted: Mon Nov 26, 2007 8:19 am
by helen&tony
Hi
I'm not sure how each individual system works, but I believe that some of them even suck the coolant from a reservoir
Helen

Posted: Mon Nov 26, 2007 9:06 am
by nfn
Hi BournemouthKen,
The coolant refill systems that I've seen attach on top of the expansion tank. Once a vacuum is created, you switch a lever so that the vacuum is replaced by the contents of a container of premixed coolant.