GROUP 4 AXLE GROUP 4 AXLE 1. TROUBLE SHOOTING 1. TROUBLE SHOOTING 5-33 Problem Cause Correction Loss of brakes 1. Incorrect adjustment 2. Brake discs worn out 3. Incorrect brake fl uid 4. Loss of brake fl uid 5. Overheated axle causing brake fluid to vaporize (brake return when axle cools). Inspect disc thickness (see page 7-149) and if discs are usable readjust brakes to the specifi cations in the manual. Inspect disc thickness (see page 7-149) and replace if needed Replace all seals in axle and master cylinder that have made contact with the incorrect fluid and all brake hoses. If incorrect fl uid leaked into axle oil, seals and O-rings in axle must be replaced.
Inspect for and repair any leaks in outside circuit or master cylinder. If caused by incorrect brake fl uid see correction No.3. If leak is to the outside replace the O-rings between the center and intermediate sections. If leak is to the inside replace above O-rings and brake piston O-rings. See "Overhearing" problem. Soft brake pedal 6. Air in brake fl uid Bleed brakes. Ineffective safety brake 7. One or both overrides are engaged 8. Incorrect adjustment 9. Brake disc worn out Check override bolts and adjust if needed (see page 7-155). See correction No.1. See correction No.2. Overheating 10. Oil level wrong 11. Too small of a brake gap. 12. Park brake dragging. 13.
Incorrect brake fl uid in system. 14. No free-pedal at master cylin- der. 15. Restriction in brake lines. 16. Restriction in return line of brake servo system. 17. Incorrect oil Drain, fl ush and refi ll oil to proper level. Readjust brakes to the specifi cations (see page 7-155) Unlock the brake and adjust the correct gap. See correction No.3. Readjust brake pedal. Inspect for and replace damage lines. Inspect for and replace damaged return line. Inspect for and remove any fi lter, tee'd in line or any other source of back pressure from the return line. Drain, fl ush and refi ll to the proper level with oil rec- ommended.