99% of Automotive (CAR) Brake Master Cylinders have a Residual Pressure Valve. This will make it at best very very slow to try to bleed the system backwards, with some it will be impossible and / or you risk damage to the Master Cylinder. Also 95%+ of the water logged Brake Fluid found in the system will be at the Slave / wheel cylinders, so bleeding it backwards pushes all this crap fluid - along with any loose rust / corrosion - through the rest of the system, including the pressure valve in the rear subframe, brake booster if you have one and of course, the Master Cylinder. You can never be sure that all the moisture has gone. Bleeding in the method recommended by 99%+ of manufacturers (that is from the top down) will be the most effective at removing most of the water logged fluid.

No workshop manual I've ever read suggests that it is acceptable to bleed the system from the wheel cylinder / caliper to the Master Cylinder. I have a fleet of light trucks (and have done since 1986) that have had either Hydraulic or air over hydraulic. These all have residual pressure valves in the system and the factory workshop manuals are very specific that the fluid be bled from the MC to the wheels. These have been Dodges, Toyotas, Isuzi and Hino. Granted, it may be possible that some say it's OK to go the other way, but I've not come across any. The medium and heavy trucks don't ever need any bleeding - they are an air system.

But, the original question was directed at doing mini brakes, not trucks or light aircraft (which have a completely different duty of brake to automotive types and some of these use hydraulic oil, not brake fluid), for these most of the time, I use a Gunsons EasyBleed. Great, clean, fast, very cheap. Oh, and won't contaminate the system with oil from an oil can.

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Why would you have a brake system with loose rust and corrosion? Seems like a maintenance problem to me.

Thanks GT for your responce, makes more sense now

I also have a Gunsen Easy Bleed

The only thing I do not like is it makes a mess when you take the cap off

My mate has one of those suck thru bleeders now they are good
the one you plug into with compressed air

after using all other kind of systems and technics i found a used pressure bleeder like this
http://www.ate-info.de/en/products/data ... betrieben/
my best 60€ invenstment last year

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Rover 214 atm ....

Your welcome kiwiinwgtn.

I don't actually use the Easy Bleed as Gunsons recommend.

Instead of connecting it to the tyre for air pressure, I use the Oxy Bottle (via the reg!) from the Oxy set. This is the dryest Air that I have readily available. Air from your tyres will likely as not have some moisture in it. The Reserviors are not designed for much pressure, I only use ~ 5 psi.

Also, I don't usually put any fluid at all in the bottle of the Gunson's unit, but I do need to keep a keen eye on the Reservior of the MC. After bleeding, I release the pressure from the Gunson's bottle then remove the cap from the MC. No mess then It also avoids having any residual fluid in the Gunson's Bottle that can absorb moisture. If I end up putting fluid through the bottle, I wash it with Metho afterwards.

I only learnt this after the first time I used it. Brake Fluid everywhere!

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all sorted...minimick...thanks

Thanks again I will try your method with the ezy bleed.I have a good air fliter for spray painting so should be able to get dry air from that.

I have to rebleed my car brakes shortly

Ta

Bernard