Brake Bleeding

[Jim Shepherd <gates_beltguy@domain.elided>]

Don't know about cost of a pressure bleeder, but you can make a really good
one for next to nothing.  Go to a big truck dealer (IHC?) and see if you
can talk them out out two used front halfs of air brake "cans".  This half
has the air inlet bung in the center.  Also get a used diaphram from them
and the clamp that fits.  Put an air inlet on one side, install the
diaphram towards this air inlet and bolt it together with the clamp that is
used for the purpose.  Put a valve on the other side and a hose that goes
to the plate that clamps on the top of the master cylinder.  Before you
connect everything, fill the air cylinder (through the valve) with brake
fluid.  close the valve and connect the air (low pressure) and open the
valve enough to bleed the air out of the fluid side of the diapharm -
holding the valve upright.  Then hook everything up and apply the air.
Once you open the valve, you will have a pressurized brake system ready for
bleeding.  If you would happen to run out of fluid (not likely since the
"can holds about a quart of fluid), you won't introduce any air, since the
diaphram will keep that from happening.

Jim Shepherd
'59 BC150
'86 S1900 being made into a motorhome

>Date: Mon, 23 Feb 98 15:01:55 -0800
>From: <hofs@domain.elided>
>Subject: Re:Brake bleeding
>
>>I cut a piece of 1/2
>>inch CRS(cold rolled steel) to 3" by 5", drilled and tapped in the center
for
>>a 1/4NPT thread, screwed in a coupling for an airhose,  After this was done
>>cut a gasket to fit the block and cut a hole for the fitting, then set 
>>this on
>>top of the master cylinder, secured it with a C-clamp and put about 40
lbs of
>>air on it. (GM recommended 30 to 50 lbs) Then proceeded to bleed my
brakes. I
>>check the fluid level between each wheel cylinder.  So far it's worked on
>>everything I've tried it on except my Saturn, it has a plastic resovoir!
>>(harumph)  If you feel that your brake lines need to be "cleaned", Denatured
>>alcohol works very well ....It get's rid of any water and any that remains
>>will evaporate in a short while.
>
>Tim,
>Well thought out and well explained. My trouble with your device and 
>others mentioned so far is that when I'm under that car and having just 
>bled a brake, I hate like hell to crawl out and go add some fluid, and 
>consequently I push it one more time, running the master cyl out of 
>fluid, and causing myself to have to start all over again. We need that 
>air pressire to be pushing fluid into the master cylinder from a 
>reservoir. Shouldn't be hard, although the last time I looked at cheap 
>pressure bleeders they weren't very expensive. 
>John
>
>John Hofstetter  "Ol'Saline's Web Site" www.goldrush.com/~hofs
>