SEAL-O-RING 5W4856 - Caterpillar

Introduction
The problem that is identified below does not have a known permanent solution. Until a permanent solution is known, use the solution that is identified below.Problem
Illustration 1 g06301804
Fan pulley shaft
(1) 495-8003 Pulley As
(2) Collar
(3) Scratch marks
(4) Set ScrewsReports from the field stated that during the service maintenance on 3516E engine, the fan shaft has become loose inside the bearings due to the set screws wound out during operation of the engine. Due to this issue, the fan pulley and shaft assembly were pushed longitudinally (backwards) towards the engine by the force of air flow.Illustration 1 represents the fan pulley assembly (1) moved out, the collar (2) that retains the shaft in longitudinal position, scratch marks (3) obtained on the shaft due to movement, and the set screws (4) that wound out.Solution
Caterpillar is aware of this problem, but a permanent repair has not been defined. As an interim action, use the same shaft ensuring that the longitudinal position of the shaft, and the pulley assembly are correct. Use Loctite 243 threadlocker blue sealant to the threads of set screws (3). Install set screws (3) onto collar (2) and tighten set screws (3) to 28.50 N m (21.02 lb ft).