brake bleeding

[quakeholio]

I went on about this earler so I thought I would put this info up for anyone that wants info on bleeding brakes. This is not a how-to, but a list of different options.

The first is the old fashioned method, pump the brake, crack the bleeder losse, close the bleeder then repeat. It's a cheap way of doing the job, but it can be a two person job, it also eats up alot of time.

Another option is a vacume bleeder. The idea is a vacume pump pulls fluid from the bleeder nipple on the calipar. Keep an eye on the master cylinder, as if it goes dry you now have to do all that work over again. I have never tried this system, but it should be quick and clean. The bad part about it is that the pump costs about $45-50. If you do a lot of bleeding or need a vacume pump this is a good tool, but if you are only doing you bike I wouldn't bother.

A different route is injecting fluid into the calipar's bleeder nipple. I can't remembr all the details, but it is another working route.

If you only want to do one or two machines then speed bleeders are a good option. They have a valve built into them so unless there is pressure on them they are closed. It alows for just pumping the brake to move fluid through the system. Most Honda motorcycles use the size SB8125. If you are going to get them I would recomend getting SB8125L as the hose is easer to fit onto the nipple. The main draw back the these is at $7.00 a pop it can get a bit pricy to do several things with.

If you want to build something you can build a pressure bleeder. These will put push fluid from the contaner out into the master cylinder and then through the system. THIS IS THE ADDRESS for how to make a pressure bleeder. I might make one up so I could bleed the brake system on my clutch and brakes in my truck. The extra fittings shouldn't be to expensive. You could alway buy one but who would want to spend over $100 to bleed your brakes.

[CharlieT]

Cheap easy way for one-person brake bleeding. Take a piece of hose that fits tight over the bleeding screw, such as small-bore fuel line, vent line, or whatever. Stick it over the end of teh bleeder and stick the other end in a clear container such as a Mason jar, Brandy sniffer, or the wife's glass measuring cup that you stole out of the kitchen. Partially fill it with new brake fluid. Just be sure there is enough brake fluid in it to keep the end of the hose submerged so that when you let off the brake pedal, you will pull fluid back into teh system and not pull more air back into it.

Then just open the bleeder valve and pump the brakes. If there is any air in the system, you will see bubbles coming out. You can also tell how dirty/contaminate the old fluid was. Pump unitl clear new fluid is coming out or you don't see any more bubbles. Then simply tighten down the bleeder and you should be good to go.

Occassionally you run across a systm that requires pressure bleeding, like on my ols Saab. In that case, go to a drug store and get an irrigation syringe. Typically they are around a 30cc syringe. Instead of sticking the end of the hose you have already put on the bleeder valve in the Mason jar, you attach teh syringe to teh hose and simply pull the plunger and draw the fluid thru the system. Lots cheaper than some of the purpose build kits you buy at an auto parts store!!! Plus the syringes are great for water fights!!

OBTW, either way you do it, make sure you don't forget to keep the master cylinder full of fluid or you will introduce more air into teh system.

[octane]

Hi
quake said:
The first is the old fashioned method, pump the brake, crack the bleeder losse, close the bleeder then repeat

...nope, not without doing what CharlieT says to do.-)
Otherwise you'll end up sucking air back into the system,
and air is exactly what you want to get rid off.
Besides you'll pump brakefluid over your precious paintwork, and brakefluid is as good a paint-remover as they come.-(

...the vacuum bleeder works fine, and along with the injecting-method
it's probably the best way of doing it after a complete rebuild when
brake-cylinder, hoses, calibers etc. are 'dry'.

For a brilliant overview, see this: Brake Bleeding Tips

Best regards
Octane

[BigBod]

I've just recently bled the front brakes on an old Nighthawk, I tried every trick in the book and couldn't get any pressure at all.

I finally tried the syringe method and forcing the fluid in through the nipple, worked a treat. Worth remembering.