Thrush Aircraft S2R–T660 Maintenance Manual page 157

TROUBLE
Dragging brakes. (Cont.)
Brakes are spongy or fail to
operate.
Brakes are spongy or fail to
operate. (Cont.)
6 -18
THRUSH AIRCRAFT INC - T660 TURBO THRUSH
AIRCRAFT MAINTENANCE MANUAL
PROBABLE CAUSE
Restriction in hydraulic lines or
restriction in parking brake
valve.
Worn, scored or warped brake
disc (see Fig. 6-2 and 6-3).
Damage or accumulated dirt
restricting free movement of
wheel brake parts.
Leak in system.
Air in system.
Lack of fluid in brakes.
Brake assemblies' defective.
REMEDY
Have someone apply and then
release brakes. Wheel should
rotate freely as soon as brake
is released. If wheel fails to
rotate freely, loosen brake line
at brake housing to relieve
any pressure trapped in line.
If wheel now turns freely, the
brake line is restricted. Drain
all brake lines and clear the
inside of brake line. If
cleaning the lines fails to give
satisfactory results, the
parking brake valve may be
faulty and should be repaired.
Visually check disc. Replace
brake disc and lining if
required.
Check parts for freedom of
movement. Clean and repair
or replace parts as necessary.
Check entire hydraulic system
for leaks. If hydraulic
reservoir, parking brake valve,
or wheel brake assemblies are
leaking, they must be repaired
or replaced.
Bleed system.
Check hydraulic reservoir fluid
level. Fill and bleed if
necessary.
Repair or replace as required.
Effective: 12/17/03