DRIVE AS-CLUTCH 9W0850 - Caterpillar

The retainer nuts that hold the clutch drive hubs of 7211 and 7221 Marine Transmissions are now tightened to a torque of 699.6 24.4 N m (516 18 lb ft). The application of this torque to the retainer nuts can cause a torque at the output flange of as much as 4203 N m (3100 lb ft). This is caused by the gear ratio of the transmission.
Because of these new, higher torque values, a new 6V2065 Spanner Wrench and two new fabricated tools have been made available. The new spanner wrench can be used with an 8H8548 Socket Extension and a torque wrench to tighten the retainer nuts. The new FT1553 Support Bar is used as a support for the socket extension, and to keep the spanner wrench in correct alignment while each nut is tightened. The new FT1554 Holding Fixture is used to hold each hub and prevent rotation while the retainer nut is tightened. The holding fixture fits over both hubs as shown, and has splines in one end which fit the teeth around the hub to prevent rotation of the hub. Drawings for the fabricated tools are available from your Divisional Service Manager. Use the procedure that follows to tighten the 4H7859 Nut on either drive hub.
1. Put the FT1554 Holding Fixture in place over both hubs as shown, with the end that has splines on the hub to be held.2. Put the 6V2065 Spanner Wrench on the nut to be tightened.
Special tools for clutch drive hubs of 7211 and 7221 Marine Transmission.3. Fasten the FT1553 Support Bar to the housing so the hole for the socket extension is in alignment with the hole in the spanner wrench.4. Install the 8H8548 Socket Extension through the hole in the support bar, and into the spanner wrench.5. Install a torque wrench in the extension and tighten the nut.6. Remove the tools and do the above steps again to tighten the retainer nut on the other hub.