brake problems

[Geico]

Our small town fire dept has a m35a2 and we have major brake issues again , well the brake peddle is going to the floor and no pressure on the peddle and the dash lights and head lights wont work we did have issues with the brakes locking up. I think that the master cyclinder or the brake booster are messed up but just want to find out before i start ripping it apart i have a spare master cylinder and brake booster from a parts truck.

 

[welldigger]

Pull the rubber boot back on the master cylinder. If there is brake fluid behind it the MC needs rebuilt or replaced. Is there brake fluid in the MC? If you bleed the brakes does it function and then loose pedal over time? You need to diagnose the problem before swapping parts around. For that matter how sure are you that the parts truck has serviceable parts?