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95MEXIFORD
02-05-2011, 11:51 AM
im trying to breed-out all the old fluid(it looks like burnt x3 motor oil) before i install the new front hose,calipers, etc. but i dont have a one man bleeding tool. so how do i go about breeding front and rear properly?

YZ250Rider23
02-05-2011, 01:22 PM
Easy... Change out your hoses first. Since you'll need to bleed them anyways after you change them, might as well not have to do it twice. With the new hoses on suck out as much of the old fluid as you can. A small turkey baster type thing or syringe will work. If you don't have anything to do that, it's fine, the next step will just take longer.

Now you'll gravity bleed the brakes. Fill the reservior, and open all 4 bleeders (or you could do the front and back separately if you're more comfortable with that). Now on the rear wheel cylinders especially, you'll need to be super careful not to round off the bleeders, or snap them off. Same goes for the front, be careful! They break pretty easy! So most of the time, I heat the cylinder around the bleeder first with a torch. MAPP or propane should work. I like to gravity bleed because it does most of the work for you. It'll get out a good bit of the air, and get fresh fluid in. If for some reason, one or more of the bleeders doesn't get any fluid coming out, or it's very slow, don't worry, it'll be corrected when the pressure bleeding is done. Keep an eye on the master reservoir and don't let it run dry!

Now to pressure bleed you'll need a helper. Close all the cylinders back up, and have you helper very slowly pump the brakes 3 or 4 times. Doing it too fast might aerate the fluid, and that will make bleeding a big chore. Have them hold down the pedal while you loosen the RR bleeder. Fluid will come out, and when the flow is beginning to slow down, close it back up. Have them let up on the pedal and push it back down. Continue this until no more air appears in the fluid, and you have fresh clean fluid coming out. Repeat this for the LR, RF, and LF, in that order (again, keep an eye on the fluid level!!). Check for leaks, make sure your fluid's full, and you're done!

trail B2
02-05-2011, 02:41 PM
If you put a piece of vacuum tubing on the bleeder screw once you flush the fluid.As always starting from the RR with the vacuum hose on the nipple of the bleeder and the other end in a container of water crack the bleeder and slowly pump the pedal a few times.The hose will not pick up the water the water will keep air from coming back into the system.This eliminates the need for a second person if you don't have anybody.

95MEXIFORD
02-05-2011, 03:04 PM
thanks fellas, i guess the main question was do i open just the front 2 bleeders or open all 4 at the same time. so your saying its up to me. well im going to start on it 1st thing in the AM so if i run into anymore problems il hit you guys up again. and to "Trail B2" thats a great piece of advice for me. especially since i cant count on my ol' lady to help me.... but if you guys have time tomorrow, could you check on here , incase i do have any run-ins... thanks again