CONFIDENTIAL TIBU4630-00
TECHNICAL INFORMATION BULLETIN |
September 21, 2005 |
Articulated Trucks |
725 (AFX1-Up, B1L1-Up), 730 (AGF1-Up, B1M1-Up), 730 EJECTOR (B1W1-Up), and 735 (AWR1-Up, B1N1-Up) |
Component Code(s) 3256, 3258 |
SUBJECT: 725, 730, 730 EJECTOR & 735 Articulated Trucks, Pinion Locknut for Field Service
PROBLEM:
Recommended change in the pinion locknut used for field service
SOLUTION:
AVSpare recommends using a 184-4265 Locknut with 196-7878 Bolts in place of the 250-7858 Locknut for field service. The 250-7858 Locknut is used to secure the pinion gear in the differential and bevel gears on the axles identified in Table 1.
Table 1
Effected Differential and Bevel Gear Groups |
|||
Machine |
Front |
Center |
Rear |
725 |
147-6790 |
188-1406 |
147-6790 |
730 & 730 EJECTOR |
147-7380 |
188-1408 |
147-7380 |
735 |
Not Applicable |
Not Applicable |
175-0336 |
Illustration 1
184-4265 Locknut with 196-7878 Bolts
The 196-7878 Bolts have pre-applied thread lock compound. When installing the 184-4265 Locknut it is recommended to apply 9S-3263 Thread Lock Compound to the treads of the 196-7878 Bolts. If 196-7878 Bolts are not available, then 3F-8156 Bolts are a direct replacement. The 3F-8156 Bolts do not have pre-applied thread lock and 9S-3263 Thread Lock Compound must be applied to the threads.
INSTALLATION PROCEDURE:
- Ensure that the input pinion bearings are adequately lubricated with oil then install the new locknut.
- Tighten the locknut against the washer. Rotate the pinion several times while tapping the top of the pinion gently with a soft mallet to ensure that the bearings are fully seated. It may be necessary to tap both ends of the pinion shaft to ensure that the bearings are fully seated.
- Continue to tighten the locknut until the rolling torque for the pinion is approximately 2.25 Nm (20 lb in). Rotate the pinion several times while tapping the splined shaft side with the soft mallet until the rolling torque is maintained at 2.25 Nm (20 lb in).
- Loosen the locknut.
- Re-tighten the locknut until the rolling torque is between 0.67 Nm (5.93 lb in) to 1.35 Nm (12 lb in). Rotate the pinion several times while tapping the shaft with the soft mallet until the rolling torque is maintained in the 0.67 Nm (5.93 lb in) to 1.35 Nm (12 lb in) range.
- Recheck the rolling torque. While measuring the rolling torque, make sure it does not "spike" or increase over 1.35 Nm. If there are spikes over 1.35 Nm (12 lb in) go back to Step 5 and use a smaller rolling torque value.
- Tighten the four locking bolts to 30+/-7 Nm (22+/-5 lb ft). Tighten the bolts at least twice to ensure that the torque has been maintained on all four bolts. Measure the rolling torque.
NOTE: The torques that are specified are for new bearings. For used bearings, limit the applied torque to one-half of the specified torque, 0.67 Nm (3.00 lb in) to 0.67 Nm (5.93 lb in).
NOTE: The torque on the four bolts is critical to the locknut holding capacity.
NOTE: An increase in preload torque of 2.5 Nm (22 lb in) can occur after tightening the 4 locking bolts on the adjusting nut for the pinion bearings. Max preload torque is 4 Nm (35.4 lb in).
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