Self-locking nuts

Self-locking nuts

Self-locking nuts, i.e. nylon insert or deferred thread nuts can be re-used providing resistance can be felt when the locking portion of the nut passes over the thread of the bolt or stud.

CAUTION: Do not apply heat in an attempt to free deferred thread nuts or fittings; as well as causing damage to protective coatings, there is a risk of damage to electronic equipment and brake linings from stray heat.

When tightening a slotted or castellated nut, never loosen it to insert a split pin or locking wire except where recommended as part of an adjustment. If difficulty is experienced, alternative washers or nuts should be selected, or the washer thickness reduced.

Where self-locking nuts have been removed, it is advisable to replace them with new ones of the same type.

NOTE: Where bearing pre-load is involved nuts should be tightened in accordance with special instructions.

FLEXIBLE HYDRAULIC PIPES AND HOSES

WARNING: Do not disconnect any pipes in an air conditioning refrigeration system unless trained and instructed to do so. A refrigerant is used which can cause blindness if allowed to contact eyes.

• Before removing any brake or power steering hose, clean end fittings and area surrounding them as thoroughly as possible.
• Obtain appropriate plugs or caps before detaching hose end fittings, so that the ports can be immediately covered to prevent the ingress of dirt.
• Clean hose externally and blow through with airline. Examine carefully for cracks, separation of plies, security of end fittings and external damage. Reject any faulty hoses.
• When refitting a hose, ensure that no unnecessary bends are introduced, and that hose is not twisted before or during tightening of union nuts.
• Fit a cap to seal a hydraulic union and a plug to its socket after removal to prevent ingress of dirt.
• Absolute cleanliness must be observed with hydraulic components at all times.
• After any work on hydraulic systems, carefully inspect for leaks underneath the vehicle while a second operator applies maximum brake pressure to the brakes (engine running) and operates the steering.