How to Build a Brake Fluid Power Bleeder
- Difficulty: Easy
- Avg. Time Necessary: 1-2 Hours
- Cost: $50-$80
Tools / Materials Required
- Brake Fluid Reservoir Cap
- Tire Valve Stem
- (2) 1/4" Brass Hose Fittings
- Bottle or Jar with tight lid
- Dremel w/ Drill and Grinding bit
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 copy from.
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