TM10-3930-660-34 10-3 DISC BRAKE ASSEMBLY - REPLACE/REPAIR (Cont’d) 2 REMOVE TWO BLEEDER SCREWS (8) FROM HOUSING. (6) 3 REMOVE TWO CYLINDER HEADS (10) a Remove plug (9) and fitting (15) from two cylinder heads (10). b Use an open-end wrench on the two flat areas on top of cylinder head (10) Remove two cylinder heads (10) from housing (6). c Remove and discard O-ring (11) from each cylinder head (10). 4 USE A WOOD BLOCK OR DOWEL AND PUSH  ON TWO PISTONS (5) TO FORCE PISTONS OUT FROM THE MOUNTING SIDE OF HOUSING (6) TOWARDS DISC SIDE 5 REMOVE FOUR DUST SEALS (12) FROM HOUSING (6) 6 REMOVE FOUR O-RINGS (13) AND FOUR BACKUP RINGS (14) DISCARD O-RINGS (13) AND BACKUP RINGS (14) CLEANING See Cleaning Instructions, para 2-10 INSPECTION 1 INSPECT PISTONS (5 AND 7) a.  Inspect pistons (5 and 7) for scratches and rust Use emery cloth to remove small scratches and rust Discard parts if there are large scratches or amounts of rust b.  Measure outer diameter of pistons (5 and 7) Discard pistons if the outer diameter is less than 2 995 inch 10-5