Brake Bleeding - Do it yourself - Technical Articles

Posted February 21, 200223 yr

comment_3306

This was posted to our mailing list by steve j daniels,

Hey folks;

I saw all of the talk about brake bleeding kits. The

speed bleeders are pretty cool, I checked out their

web site, and I think the idea is sound, but it'll

cost you 31 dollars a car (seven dollars a bleeder and

3 dollars shipping).

I have a Mighty Vac, I thought that was pretty cool

for a while also. But if you ever used one, you know

that sooner or later you'll run into the situation

where you have to empty the reservoir and you end up

spill brake fluid all over your hands...worse yet you

pump brake fluid through the "pump head", and over

time brake fluid softens and swells the rubber hoses

and "fittings". I ended up just using the reservoir

and a rubber hose.

Here's an inexpensive Do It Yourself brake bleeding

Kit.

1. A 16 ounce plastic soft drink bottle and cap.

2. A 2 to 3 foot length of rubber vacuum line or wind

shield washer hose. It can be longer if you want.

3. A length of 2x4, I use an aluminum baseball bat.

I'll get to that explanation.

Now, take your hose and the plastic soft drink cap,

look at the hose and choose a drill bit size that will

allow you to drill a hole in the cap that will give a

tight fit when you pass the hose through the cap. You

don't want the hose to pull out of the cap easily.

Next, drill another very small hole it the cap, this

will be a "pressure relief" hole, a sixteenth of an

inch is good.

Screw the cap back onto the bottle and push the hose

home until it touches the bottom of the bottle.

If your bleeder is working and free, put a box end

wrench on the bleeder, then push the end of your hose

onto the bleeder. Crack open the bleeder a quarter to

half a turn. Set the plastic bottle on the ground

standing straight up. Now you can start pumping the

pedal, slowly please. "I like to pump out almost all

of the old fluid first, our you can take an old

kitchen baster and suck out all of the old fluid first

and top up with new fluid to start with. But anyway

the idea is to get all new fluid throughout all of the

brake system.".

The idea here is to pump in enough fluid into the

bottle so that the end of the hose is submerged, you

pump until no more air bubbles come out of the hose

end. Now this is where the length of 2x4, or baseball

bat comes into play. Push the pedal all of the way

down to the floor and place/wedge the 2x4 between the

pedal and the seat cushion. "I can't tell you how long

that is, I've never bothered to measure this, you'll

just have to figure that out for yourself." Now you

can close the bleeder screw. Don't forget to watch and

top up the reservoir, or else you'll pump air into the

system and you'll have to start over.

Brake fluid will attack the rubber hose that you use

and you will loose the tight fit that you want, but

this is so inexpensive, you just replace the hose when

that happens.

Bleeding sequence.... convention has it that you start

with the bleeder farthest from the master cylinder and

work back. This is for Dual Circuit Systems. Some

cars, not many, have Triangulated Systems, such as

Volvos. Volvos have four disc brakes and eight

bleeders screws, three on each front caliper, and one

on each rear caliper. In Volvos case you do need a

"map", you have to follow a set sequence of bleeding

or else you are just pounding sand.

Eh, I know that was a lot of words to describe a

simple operation, but what can I say, I don't have an

editor.

Steve J. Daniels