What is intermediate shaft lubrication?
Short answer
| Lubrication type | Medium | System | UR Z21 section |
|---|---|---|---|
| Oil lubricated | Mineral oil | Closed | §2.3 |
| Water lubricated | Seawater | Open | §3 |
| Closed-loop | Fresh water | Closed | §2.4 |
- Definition: lubrication of the bearings that support the intermediate shaft between the main engine and the propeller shaft
- Three system types: oil lubricated, water lubricated (open seawater), closed-loop fresh water
- Governing instrument: IACS Unified Requirement Z21 §2.3, §2.4, §3
- Trap: open seawater systems must not pollute; closed-loop fresh water avoids oil-to-sea interface
- As Second Engineer: verify system operation, monitor bearing temperatures and lubricant condition, ensure UR Z21 compliance, record in PMS
Full answer
The full answer explains each point step by step, with the regulations and figures behind it and the discussion from other candidates. It is in the MEO Class II section of the Marine One forum, open to members enrolled for the MEO Class II exam.