to build you own brake fluid power bleeder
There are several
brake system flushing methods. Traditionally this is a two person
job, one open the valves at the brake caliper and one person pumps the
brake pedal. The draw backs of this method is that there are some
possibility damage could occur to the master cylinder piston, the believe
is that the piston rarely travels to the extend on a normal usage compare
to when it is being pumped all the way down to the floor the dryness and
the roughness of the piston may puncture the seal. Personally I have
never seem this happen, but better be safe than to be sorry. A simple
power bleeder consist of just the extra reservoir cap and a spare tire
to pressurize the system, the disadvantage is that you will need to open
the cap often to keep the fluids filled. The power bleeder I made
here is a equivalent of a $150 unit sold out there, it does not require
you to open the cap at the reservoir to fill up the fluid, and only one
person is needed to operate it. This system shown is designed with
the use of a air compressor with an adjustable regulator, but with minor
modifications it will also work with a spare tire.
All the parts required
to build this power bleeder can be purchased at your local Home Depot and
Walmart for less than $60.
My home made power
bleeder works by compressing the new brake fluid from the supply bottle
through a custom made brake reservoir cap that replaces your stock reservoir
cap and pushes the new brake fluid through your brake system and out at
the bleeder nut on the caliper.
P.S. I will
trying the system out for the first time next week..... So far I have only
pressurized the system and it holds the pressure at 20 psi, there are no
reason why this home made system would not work, it is an exact copy of
the $150 system sold out there. But I will keep everyone informed
if it doesn't....
You will need to
start with an extra brake fluid reservoir cap for you car. You can
purchase it from your local Porsche dealer.
This is about as
far apart as you can take apart the cap.
The white plastic
pieces needs to be widen the plastic float needs to be discarded in order
for the rubber valve stem to fit through.
A hole will need
to be drilled on the black cap in order for the valve stem to fit through.
This is how the
completed unit look
This is where the air
source connects, this same point can also be exchanged with a valve stem
connector to connect to the spare tire. In this case I am connecting
it to my air compressor.
You will need to find
a brake fluid supply bottle which will hold the extra brake fluid to be
pumped to the brake reservoir when it is bleeded out, I found mine at Walmart
at their "Camping equipment" section. The bottle has a tight seal
and will hold at least 20 psi of pressure. Two holes need to be drilled
to accommodate the connectors one which will be connected to the air source,
the other to the custom made reservoir cap. Besides drilling out
the hole I also used the Dremel to smooth out the edges.
All the fitting
are from Home depot from their air tools parts section. these are
all air hose connectors and adapters.
I first completed the
system without any rubber washers and found out pressurized air leaks out
around the connector area. Some rubber seal was purchased from Home
Depot at their "sink" section of the store and I installed them on
both the top and the bottom of the connectors.
Here is a picture of
the completed cap, the air inlet compresses the bottle with compressed
air, and the only way pressure to exit the bottle is through the clear
rubber hose on the other connector which will be hooked to the custom made
spare reservoir cap via the valve stem.
I used tape seal on
all the fittings to prevent any leaks. This is a picture of the valve
stem quick connect which can be hooked and lock on the valve stem of the
custom made reservoir cover. The other end of the brass connector will
connect to the outlet of the brake fluid bottle.
Here is a picture
of the completed unit.
Thank to Hank Cohn
for buying the $150 new unit....... it provided a good example for me to
The Coleman bottle
I used in this DIY does not hold up under pressure, it will break!
You will need to find a stronger bottle for this DIY
Update June, 2003
E-mail received from Bill J.
|From: Bill J.
Subject: Power Brake Bleeder
Sent: Mon, 2 Jun 2003 13:57:06 -0400
I built a power bleeder this past weekend
and to answer your needs as to a better bottle - I used a radiator overflow
bottle from a wrecked Audi. It was perfect - having a fitting at the top
of the container for the air compressor, a fitting at the bottom for the
brake fluid. The cap had a safety valve which would limit the pressure
in the container. I suppose any radiator overflow container will work -
one thing I would suggest when picking one is to get a flat bottom so it
is stable when one sets it down.
Hope this helps