ADAPTER AS 7M8489 - Caterpillar

LOADERS
988F (8YG),
988FII (2ZR),
992D (7MJ),
994 (9YF)Problem:
We have received some Cartridge Pin failure reports. Analyzing some of these failed pins; we could establish the following major failure modes:- cartridge pin bearing/Shell crushing- seal leakage- seizures- lack of recommended lub/service intervals- wrong viscosity- wrong/poor quality oils used. Discussion:Cartridge pin crushing can be a result of over-torquing the lift arm nose bolts or the dog bone split end bolts. This failure mode can be aggravated by tolerance stack ups. Seal leakage can be a result of cartridge bearing/shell crushing. If the bearing rubs on the pin is due to over-torqued bolts, debris is generated, which can chew up the seal assemblies. Pin seizures can be a result of loss of oil - hence - leakage - failure to observe the service intervals for flushing/refilling - or again, due to bearing shell crushing. Pin overload aggravates this failure mode. The higher the load factor, the more frequent the service interval should be. Solution:
Cartridge pins are precision parts and should be handled , installed & service as such ! It is important to treat the collets, in & outside (994 inside only) as well as all the bolt threads with anti-seize compound before installation. All other surfaces and bores should be clean and dry. Do not use an impact wrench to finish tighten the bolts.The torque SPEC for the lift arm nose clamping bolts is standard torque. Do not overtorque these bolts. It is best to go only to the minimum SPEC and use a well calibrated torque wrench.The main collet clamping bolts/rod as. need to be correctly torqued, and then retorqued after 10 and 50 hours of machine operation. IMPORTANT ! Use only hardened washers or the bolts/rod as. will come loose.Furthermore it is recommended to flush/refill the cartridge pins every 1000 instead of 2000 SMU's as stated in the OMM guide. (Reducing the service intervals will reduce the risk of seal damage due to generated debris). To do this, remove both, inner an outer 6V2766 plugs, install a special fitting (OMM guide ref) into each pins outer end and pump (with a clean grease gun). Gear Oil through each pin, until they are thoroughly flushed. After the pins are refilled with clean G-oil, replug with the 6V2766 plugs. It is important that you enter every incident correctly & timely into SIMS. We plan to send out more PRR's for further analysis - please keep the iron available especially the "early hour" incident which were paid under warranty. CATERPILLAR MINING AND QUARRY BUSINESS UNIT COPYRIGHT 1995 CATERPILLAR ALL RIGHTS RESERVED