I have a 2001 Rancher 350 4x4 and it currently has no brakes. I can pump them rapidly 8- 10 times and they work once but once I let off they need to be pumped again. I just replaced the master cylinder today, thinking that may be the problem, but it has not helped. We have continued to bleed the brakes, but there is always more air in the lines and we don't know where it's coming from there are no visible leaks or fluid loss. Anyone have any thoughts on what may be wrong, or different routes to go in fixing it? I am pretty new to the world of four wheelers, this is my first one, so I'd really appreciate anyone's input who has more experience than I.

 

it sounds like you have air in the line, and since you replace the master cylinder, i would rule that out. Try bleeding the air from the lines and see if that helps. If that doesnt, take a look at the inside of the brake drums. Dont pump the brake with the drums off, you'll blow out a wheel cylinder, but the wheel cylinders might be bad. also try adjusting the brakes up, if they got rusty they probably wore out fast.

if you could find a way to block the ends of the brake lines after taking them off the wheel cylinders, then try it. If you have pressure then, then it's probably in the wheel cylinders or brake assemblies. If you still have no pressure, then you have air in the line or another bad master cylinder. could be collapsed rubber hoses too.

 

I had an older 300 4X4 with the same problem. In my case, it was the cyliders like "quicksilver" said. I had one of the two cylinders on each side locked up. If it is the same as my old 300, the cylinders have adjustment screws to push the brake pads out towards the drum. If you can screw these out and the pads move out than your cylinders may be ok. If they don't turn or they turn but the pads don't move then they need to be replaced. Once I replaced the cylinders and the pads, all was well again.

Good Luck

Cirviver