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'78 Yamaha agin' hope you guys arent sick of me coz I got more questions coming.

Now I removed my rear mamster cylinders, removed the piston etc, sprayed it with brake cleaner and had a whole lot of sediment come out. I made sure the lines and the cylinder were completely clean and free of sediment and that the cleaner flowed freely through all openings. Now that I reassembled it, and tried to bleed the system, the brarke fluid just stays in the reservoir. I thought the bleed valve was not loose enough, so I even remomved the cable off the calipers, but the fluid wont leave the reservoir.

I;ve also pumped the brake lever a number of times.. no soap cant imagine whats wrong here. Im quite positive there's nothing clogging the lines or fluid recesses in the cylinder assembly. With the brake line disconnected from both ends, shouldnt brake fluid just flow out onto the ground as I keep pouring it? whts wrong with this picture???

Thanks

Brake fluid shouldn't necessarily drip out like that - those holes are pretty tiny. Make sure your banjo fitting is correct, MAKE DOUBLE SURE your holes aren't clogged (Use pressurized air if you have it) Also, if you didn't take the rubber bitsw out of the cylinder pefore putting brake cleaner in, the brake ckeaner may have turned the rubber bits into mush...

yup I completely disassembled the MC and put everything back correctly (OK now im relatively sure of this). But I did also test that brake cleaner comes thru the holes (I used an aerosol cleaner), so yes it did have some pressure whiilst cleaning. I guess I just will have to do it again.

I reused my MC parts, spring piston etc, coz they seemed good. All I needed to do was have one MC workinig so I could pump the piston out of the caliprs (One o my prerv posts) got too impatient waiting for my good MC rebuild kit to arrive in the mail.

Make sure that the end of the line isn't open while you let the brake pedal back up. Pump the brake, and then open the line, then close the line before letting up on the pedal. This way the master cylinder isn't just sucking air up the line when you release the pedal.

Yup thts it i gues. Completely forgot about surface tension!!!