Brake issue

[coachdog]

I have a 1987 Mallard Sprinter class a motorhome. It has the Chevy P30 chassis with the 454. My brakes are very spongey and barely stop the coach. The brake pedal goes all the way to the floor and the brake light comes on before it slows down at all. I'm thinking that the brakes need to be bled or a seal is bad. Any suggestions?

[87Rockwood]

Check your master cylinder and brake lines for leaks.

[GNP99]

Most likely it is the master cylinder. Brake fluid absorbs moisture over time, it sits on the bottom of the master cyl and corrodes the surface causing the fluid to bypass. Replace the master cyl and bleed brakes using lots of new fluid to flush out the system. Had the same problem with my old 1984 Winnebago P30 454.