B737 MAX Series Undifferentiated
Maintenance Airframe; Maintenance Powerplant
Troubleshooting; Time Pressure; Confusion; Communication Breakdown; Workload
Aircraft Equipment Problem Less Severe; Deviation / Discrepancy - Procedural FAR; Deviation / Discrepancy - Procedural Maintenance; Deviation / Discrepancy - Procedural Published Material / Policy
General Maintenance Action
Aircraft; Equipment / Tooling; Human Factors; Manuals; Procedure; Staffing
Was assigned to perform the multiple tasks for aircraft return to service after extended parking. During accomplishment of the tasks had to open the engine cowls and more specifically the thrust reverser cowls. The station currently has hydraulic cowl pumps using XXXX oil. The AMM procedure gives the tool number of a cowl pump which was correct for equipment on hand and also gives the different mil-specs of oil that can be used. The oil from my understanding is consistent with X specifications however the opening actuator for the cowl state on a placard to 'use engine oil'. The engines on that particular airplane are serviced with YYYY oil which also falls under the X specification. There was some confusion about which oil was appropriate to use for this situation since the engines use YYYY oil but cowl pumps on hand had XXXX oil and the  specs were the same for both oils. We ended up taking a XXXX oil cowl pump to the tooling department at ZZZ; draining it; cleaning/flushing it; replacing the filter; relabeling it with YYYY oil and servicing it with that oil for use on the aircraft. There was just some confusion about the proper oil.
Technician reported confusion in reference data during return to service maintenance on B737 MAX stored aircraft.