Document 2NqygJ1bGpGVMZ2EdpZLYwk1g

LOOKING INSIDE THE BRAKE DRUM Another method of adjustment commonly in use is to adjust by push rod travel, but here you should first establish conclusively what push rod travel would give a free brake. Then you can subsequently adjust by travel without raising the wheels. The measured push rod travel is the difference between the fully applied and released positions of the brake. Leverage The angle of the push rod and slack adjuster should be checked with the brakes fully applied. The angle should not be less than 90" for air or greater than 90* for vacuum. Movement beyond center drastic ally reduces the brake effectiveness as it shortens the effective length of the lever. Such a condition calls for readjustment. While on this subject of brake adjustment, be cer tain that the initial adjustment at time of reline affords extra lining to drum clearance because of the minimal lining swell that is inherent in all lin ings irrespective of manufacturer during the breakin period. A clearance of .020 between lining and drum should be adhered to on a newly relined vehicle. After the break-in period the normal .010 clearance would be the rule. All brake adjustments should be made with cold drums and more frequent adjustments are recom mended for more effective braking as well as leng thening the life of the brake components because of minimum movements. Completing The Job Now you may feel certain that you have a safe stopping unit but actually the brake job is not yet completed. An air gauge should be employed to check out the air system for responsiveness and especially to ascertain the air delivery pressure to each chamber. The delivery pressure phase is most important, and particularly so in a panic stop where the availability of maximum air delivery can mean the difference of a few or several feet in the stop. The completely restored brake system should afford uninterrupted service until the need to reline again. i n SPNY 006016