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Discussion Starter #1
just installed a new rear caliper, ss brake line, and rebuilt the master cylinder..ive tried bleeding in 6 times now. replaced the banjo bolts, the copper rings, took apart the master cylinder. and still can not get the rear brakes to work.. anyone ever have this trouble or know of a solution?
 

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6 separate sessions or just six times? Took me a while to do my new front lines with duals coming from the master. I eventually got it and is pretty good right now. U also use a large syringe with a tube for the nipple and force suck the air out. You can also force fluid in with this method.. I haven't tried that way yet but may soon. Or gravity feed.. Crack the nipple and wait for fluid to come out unless it already is.
 

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Discussion Starter #3
had the same trouble with the fronts but they work now..6 seperate times with prolly 12 to 15 bleeding processes..just doesnt want to pump..the pedal is all air..i get fluid coming out from the bleeder but the little filler bottle never seems to drain i fill it enough to wear it spills out when i put the lid on but nothin is happenin..ill have to try the syringe deal..now with the do you fill the bottle close it ...or leave it empty close ??
 

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Have you tried filling it backwards?

Get a pliable bottle attach, glue or melt a tube to it and force feed the nipple from the cylinder until it fills the open master cylinder.

Also this way you could hang a 2 liter bottle full of brake fluid higher than the cylinder and let gravity do its dirty work for you. When your ready just poke a hole in the hanging bottle and it should fill it up and watch it so it dont spill.

Just a tought...It might work.
 

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Leave the lid off so you can see it fill. Try to force suck it out also.. Its the easiest. They make brake kits for this but a utility syringe is the cheapest. Make sure the rubber cap from under the lid is out too lol just another thought
 

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Master of the Electron
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Unbolt and raise the caliper above the master cylinder - dang air bubbles like going uphill but are a pain to make go downhill in that small brake line.
 

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Discussion Starter #8
tried everything you guys said wasted a big bootle of brake fluid still cant get it to pump...took the mastercylinder apart again blew everything out with the air compressor and still can not get any pumping action..only thing i can think is maybe buy a new master cylinder body or change out the stainless line...any thoughts
 

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Master of the Electron
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All of our suggestions depend upon working components (which we would assume is the case, because they are all new/rebuilt).

The most likely issue is the master cylinder, since YOU rebuilt it... no offense intended. With the brake line disconnected does it pump brake fluid? If not then your rebuild is the suspect. Did you hone the cylinder?
 

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tried everything you guys said wasted a big bootle of brake fluid still cant get it to pump...took the mastercylinder apart again blew everything out with the air compressor and still can not get any pumping action..only thing i can think is maybe buy a new master cylinder body or change out the stainless line...any thoughts
How did you waste all this brake fluid if the master cylinder doesnt pump...........
 

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Discussion Starter #11
quad..i disconnected it and it will pump up fluid and pressure i stick my finger over it and it blows out as i pump...willy i tried bleedin the brakes alot !! but tonight i did the gravity method i got fluid from the caliper up to the ressy no air ! everything got tighten up then started pumping...but pumpin does nothin.. the piston moves back and forth about 3mm just enough you can see it move. but thats all it will do..its just pumpin air ! so does that mean the body of the master cylinder is shot ?
 

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quad..i disconnected it and it will pump up fluid and pressure i stick my finger over it and it blows out as i pump...willy i tried bleedin the brakes alot !! but tonight i did the gravity method i got fluid from the caliper up to the ressy no air ! everything got tighten up then started pumping...but pumpin does nothin.. the piston moves back and forth about 3mm just enough you can see it move. but thats all it will do..its just pumpin air ! so does that mean the body of the master cylinder is shot ?
If you hold your finger over the hose and it pushes your finger off, this is a good sign............
It sounds a s if you may two problems, air in the brake cylinder and the oring that seals the piston to the cylinder is holding the piston from moving freely, and acting like an elastic band and pulling it back after you let the brake go...........
 

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Discussion Starter #13
that does happen when you let the brake go the fluid goes back...so ur sayin its an oring issue ? i just used the original oring it looked okay maybe get a new one and try it
 

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that does happen when you let the brake go the fluid goes back...so ur sayin its an oring issue ? i just used the original oring it looked okay maybe get a new one and try it
Take the pads out and pump it so it travels out farther without having to do any work. Then squeeze it back in and this will also push the air out.
 

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Discussion Starter #15
i tried that it wont go out at all...its out about an 1/8'' and just goes back and forth slighty just so you see it move thats all it will do..
 

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i tried that it wont go out at all...its out about an 1/8'' and just goes back and forth slighty just so you see it move thats all it will do..
Okay, try this. Squeeze the brakes and put a pair of pliers on the hose. Them let the brake go and resqueeze the brakes and let the pliers go at the same time. Do this several times to force fluid into the brake cylinder.
 

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Discussion Starter #17
i tried that little trick it actually worked however when it gets tight it kinda stops pumpin before i could lock up my brakes now its kinda like a rolling stop...do you think taking the pads out pump the piston out and pushing it back in would help that to make it more solid...
 

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i tried that little trick it actually worked however when it gets tight it kinda stops pumpin before i could lock up my brakes now its kinda like a rolling stop...do you think taking the pads out pump the piston out and pushing it back in would help that to make it more solid...
Yes, pump out the brake piston as far as you dare, measure the thickness of a worn set of pads plus the rotor, and you could pump them out to that dimension............
Then squeeze the piston back in..........................
 

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Discussion Starter #19
hmm i shall try that..now any good advise on a good clutch for the 727 big bore...i cant keep a clutch in that thing to save my life...
 
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