Ford F-650 2008 User Manual page 164

Maintenance and Specifications
on original equipment chambers now incorporate a stroke indicator to
aid in adjustment checks; an orange paint marker near the base of the
push rod. If the push rod is clean and the brakes are out of adjustment,
the orange marker can be seen protruding from the chamber when the
brakes are applied.
Do not manually adjust the automatic slack adjusters to correct
excessive pushrod stroke as it may result in reduced brake
effectiveness and a vehicle crash. Excessive pushrod stroke indicates
that a problem exists with the automatic adjuster, with the installation
of the adjuster, or with foundation brake components that manual
adjustment will not remedy. Seek service from a qualified facility for
excessive pushrod stroke.
Inspect the brake lining every maintenance interval. When brake lining or
blocks are worn to within 1/16 inch (1.6 mm) of rivets, brake lining must
be replaced. This inspection or adjustment should only be performed by
a qualified technician and must be in accordance with instructions
provided by the service manual.
Do not back off or disconnect the front brakes so that they are less
effective, letting the rear brakes do all the stopping of the vehicle. Do
not overlook the brakes on the trailer, either. Brake condition on the
trailer is just as important as the tractor. Proper brake balance on trucks
and tractor-trailers is essential for effective braking.
Once a year, the entire brake system must be inspected. Check the
following:
• Any rubber as it may deteriorate whenever used. Rubber brake
components should be inspected by a qualified technician and
replaced as necessary. Replacement intervals vary according to the
severity and length of vehicle service.
• Condition of brake drums, brake chambers and slack adjusters.
• System for air leaks.
• Hose or pipes for rust, damage and deterioration.
• Operation of service and parking brakes.
Some parts such as air brake chamber diaphragm, air compressor and air
cleaner should be inspected periodically and replaced if considered
unserviceable.
164
2008 F-650/750 (f67)
Supplement