If you've noticed an error in this article please click here to report it so we can fix it.
With reference to the article by "Preceptor" on brakes CM February 24), there are paragraphs on page 52 in column one which are incorrect regarding the relation between brake pedal travel and brake adjustment.
The amount of brake pedal travel is in no way related to brake lining and drum clearances in a full air-operated braking system, as the pedal is operating an air valve only, and controls the amount of air pressure passed to the actuators (brake chambers).
Therefore, the article could be misleading to anyone not fully understanding an air braking System.
Excess drum to lining clearances can be realised by the volume of air used on each pedal operation, or by checking the amount of free movement on the camshaft and slack adjuster.
H. G. WALTER, Manager, Road Freight Repairs (Devon) Ltd, Bideford, Devon.
Mr Walter is correct in his description of the operation of a full air-brake system. Preceptor's description of course, applies to an hydraulically operated brake. — Ed.