[tim2]

The four wheeler had not been ridden in about four months. I got it started and road it about 400 feet and both front tires brakes locked tight as a drum. I tore into it today and found the fluid in the reservoir was discolored like rust. I cleaned it out and took the reservoir off and tried to get fluid flowing through the little holes in the mount. Reassembled it and mounted on the bars. Now I am getting nothing at coming out of the connection for the hose. I am hoping someone on here can point me in the proper direction. The brake lever was VERY hard to pull before I took it for a ride, now the lever works freely but is NOT pumping any brake fluid at all. HELPPPPPPPP

 

[tim2]

I just pulled the plunger out of the master cylinder, thinking it needs new seals. At first the brake lever would not move at all, when I rode it they locked up. I bled the calipers and the lever started moving freely but will not build any pressure. So it looks like it will be Tuesday before I can buy a set of seals for it. If anyone has another suggestion PLEASE shot me a reply.

 

[hatzie]

Sounds like you're on the right track. I'd check the bore for corrosion. If it's pitted or scored the new seals will get ripped up in short order.
There are return springs in some motorsports master cylinders as well. So. That rust colored fluid may not just be corrosion from the lines and calipers... It may be the remnants of the return spring(s).
On automobiles you usually need to "bench bleed" the master cylinder before you install the lines. Google "Bench Bleed ATV master cylinder".

Rust never sleeps. This is why I flush the brakes on everything I own every 2 years. It's cheap insurance. Brake fluid picks up water from the air even through rubber and plastic. Water lowers the boiling temp of brake fluid substantially. Water encourages corrosion too. Discolored brake fluid is corrosion from inside the brake system suspended in the water contaminated fluid.

 

[tim2]

Well I have been attempting to locate the plunger seals online and have no success at all. I do not think the local (50 miles away) dealer opens until tomorrow. I have already tore down the calipers and hoses and cleaned them very well. I am now getting great looking fluid flowing from the lines. If anybody has an idea of where online I can get just the seals please post or email me a link to the site.

 

[tim2]

I just got off the phone with the Polaris parts people. They do not sell the seals for the front master cylinder and recommend replacing the entire master cylinder at a cost of $203.99 plus tax. So I guess I need to start searching for a used master cylinder. If anyone has one laying around they could get rid of drop me a line.