Major Overhaul
Liners, pistons, bearings, crankshaft inspection and the associated cooling and injection work, carried out in a yard or on board where access allows.
Features
- Planned well ahead, because the parts, the access and the yard slot all have lead times of their own.
- Crankshaft is measured and, where necessary, ground, and the bearing sizes then follow from that measurement.
- Cooling passages and coolers are cleaned and tested while the engine is open, since a rebuilt engine in a fouled cooling system runs hot.
- Auxiliary items such as turbocharger, pumps and injection equipment are dealt with in the same visit rather than left to fail afterwards.
- The rebuilt engine is run in according to the builder's procedure, and the running-in record forms part of the handover.
Specifications
| Figure | Typical range | Unit | Why it matters |
|---|---|---|---|
| Scope | liners, pistons, bearings, crankshaft | defines the job and its duration | |
| Crankshaft measurement | journal sizes recorded | mm | determines bearing sizes and whether grinding is needed |
| Location | in yard / on board | access decides what is possible and how long it takes | |
| Ancillaries included | turbocharger, pumps, injection | avoids a failure shortly after a major spend |