Usage:
Problem:
It is possible that the lower Bolts of the 70-Side-Plates come loose after a few hours of operation. We believe the reason for this is the thick paint on the Side-Plates that may lead to the torque relaxation. Originally 7Q8330 grade 8.8 bolts are installed at standard torque. Simply retightening the bolts will not solve the problem. In any case, the paint under the bolt head (washer) must be removed. For solution 2) and 3) we recommend to replace the lower bolts with CAT 7X2454 (Dacromet) or 8T0668 (phosphated & oiled) grade 10.9 bolts.
Solution:
1) Hammers still in Dlr.: inventory:
Loosen all four bolts of each side-plate (not all at the same time). Remove the paint under the bolt-head (washer). Retorque the bolts to 700± 35 Nm (520 ± 25 lbft). Reuse all bolts and lockwashers.
2) Hammers having worked for 50 hrs or less:
Remove all four bolts from each side-plate (not all at the same time). Remove the paint under the bolt-head (washer). Reinstall the upper bolts. Replace the lower two bolts with CAT-7X2454 or 8T0668 bolts. Reuse the upper bolts and torque to 700 ± 35 N·m (520 ± 25 lbft). Torque the CAT-bolts to 900 ± 50 N·m (670 ± 30 lbft). Replace all 3E6501 lockwashers.
3) Hammers having worked for over 50 hrs or having had loose bolts.
Remove all four bolts from each side-plate (not all at the same time). Remove the paint under the bolt-head (washer). Check the drilled hole in the hammer front-head and clean it out if necessary. Should a bolt have come loose and it can no longer be replaced with another bolt of the same length, it is possible that the original bolt has been torn-off. In that case the reminder of the original bolt must be removed from the front head and the threads be cleaned. Replace the lower bolts with CAT 7X2454 or 8T0668 bolts. Reuse the upper bolts and torque to 700 ± 35 N·m (520 ± 25 lbft). Torque the CAT-bolts to 900 ± 50 N·m (670 ± 30 lbft). Replace all 3E6501 lockwashers.
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When using 7X2454 (DACROMET) bolts, DO NOT lubricate the bolts threads prior to installation |
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