OPT, OK I have an 04 scrambler. I have replaced the rear caliber and pads. I have had tons of problems bleeding the system. I have to pump the hand level a couple times before it will brake. Last night I took it over to a buddy's to help me try again. When I started off I had solid brakes, about 40 seconds into the drive, no brakes, pump pump pump and I had brakes again. then the same thing. Got it over there and we bled the fronts then the back and seem to have good pressure. Went to bleed the rear with the rear peddle and got it to bleed and take pressure, then it went away. never got it back. Now my brakes barley work. I am thinking just to cap off the rear brake line that goes to the foot pedal. It was weird when I pumped the hand brake I could feel the foot brake move ever so slightly up. Also we could hear what sounded like air every time we pumped the hand brake, coming from somewhere up front, maybe the valve that all the lines go into? But no fluid was leaking anywhere. Very frustrating. Anyone have any thoughts?

 

Feeling the pedal brake through the hand brake was usually caused by air seeping past the o-rings in the rear caliper half.Since it's a new caliper it may be seeping air through the small rear brake master cylinder seals especially if you can't get this pedal to build up pressure by itself.These things are to cheap now to rebuild or pay the high dollar oem price.Brake Master Cylinder 1999-2009 Polaris Scrambler 400 500 & Magnum 325 330 500 | eBay

 

Thanks. Can i just disconnect the foot pedal line and cap at the caliper with a banjo bolt and washers? Would tgat solve it.

 

You can,but you didn't hear it from me..

 

Ok did it. Took off the rear master cylinder and brake line and plugged it. I get pressure now but when I start to drive it goes away and then I need to pump 2 or 3 times. Just throwing this out there, I thought I read on here or somewhere else that it could be something with the front wheels and the wheel bearing (maybe) that would cause a wobble in the wheel and that would then cause the brake disc to hit and push the brake caliper piston in a bit. THat would would make it so you have to pump it back to position. Any chance you have heard of that? How would I check for that if you have? Also I had it one the road today so after I brought it up to speed, hit the brakes to get them to work and start to slow down I could hear like a squealing coming from the front left, not real loud almost sounded like a belt squealing on a car.

 

Still think you either have air trapped in the system or the main master cylinder may be seeping air. Rebuild kits are available for these plus sometimes you can find new master cylinders on ebay,etc cheaper than a rebuild kit if this is what you narrow it down to.

 

Ok I bought a new master cylinder. I couldnt fine any rebuild kits for some reason. Just my luck. 😊

 

You can prime the new master cylinder by having your finger over the hole until it builds pressure,then mount to the bars and hook up the brake line. Keep the master cylinder filled with dot 4 and use a mityvac if you have one. Makes short work of brake bleeding.

 

Thanks. Dot 4? I have been using 3. Does that matter?

 

Dot 4 is interchangeable with dot 3 and better fluid. If you have dot 3 no harm in using it up.