Chapter 5 General Reference 119
3 Start vehicle, engage PTO and slowly winch loadline up until anti-two-block weight comes in
contact with the hook end of the loadline cable. At the moment the weight is fully supported,
a marked difference in winch operation should be noted. At this point, the winch up function
should become very sluggish or non-functioning and have very little pull capability. Slowly
increase truck engine speed while simultaneously actuating the winch up function. The winch
characteristics should remain sluggish with little or no tensioning of the cable. If operation
other than as described occurs, stop immediately and investigate. Failure to do so will risk
damage to the cable or the crane. If all is well at this point, actuate the boom extend function
slowly, and gradually increase to full actuation. Once again the function should be sluggish
or non-existent with no tightening of the winch cable. If operation other than described
occurs, stop immediately and reverse the function.
4 The final check involves actuating both the winch up and extend functions together and
checking for proper operation of the anti-two-blocking circuit. Once again, start slowly and
stop if it appears the cable is being tensioned.
5 If the anti-two-block function appears to be functioning normally, winch the cable down until
the sensing weight swings free.
Thread Torques
WARNING
Anytime a gear-bearing bolt is removed, it must be replaced with a new bolt of the identical
grade and size. Once a bolt has been torqued to 75% of its proof load and then removed, the
torque coefficient may no longer be the same as when the bolt was new thus giving
indeterminate clamp loads after torquing. Failure to replace gear-bearing bolts may result in bolt
failure due to metal fatigue, causing serious injury or DEATH.
When using the torque data in the torque charts, the following rules should be observed.
1 Bolt manufacturer’s particular specifications should be consulted when provided.
2 Flat washers of equal strength must be used.
3 All torque measurements are given in foot-pounds. To convert to inch-pounds, multiply by
12.
4 Torque values specified are for bolts with residual oils or no special lubricants applied. If
special lubricants of high stress ability, such as Never-Seez compound graphite and oil,
molybdenum disulphite, collodial copper or white lead are applied, multiply the torque values
in the charts by the factor .90. The use of Loctite does not affect the torque values.
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