6G70ME-B9.5
The MAN 6G70ME‑B9.5 is a six‑cylinder, two‑stroke medium‑speed marine diesel engine delivering up to 41 220 kW at 91 rpm, notable for its camshaft‑driven exhaust valve and electronic fuel injection.
Engine Specifications
Inspector Detail
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Designation decoded
6 stands for 6 cylinders, G for Green Ultra-Long-Stroke, 70 for 700 mm bore, ME-B for electronically controlled fuel injection with camshaft-controlled exhaust valve, 9.5 for Mark 9.5.
Background
The G70ME-B9.5 with 6 cylinders is the Green Ultra-Long-Stroke variant of the 70 bore class. S/B 4.65 at 700 mm bore with 3256 mm stroke. A medium-to-large engine for Panamax bulkers and mid-size tankers. ME-B technology with electronic injection. 6 cylinders for more power than the 5-cylinder version.
Calculated metrics
Inspector checklist
- Cylinder liners: S/B 4.65 at 700 mm — extremely high side forces, systematically document thrust-side wear
- Piston rings: Maximum side pressure — ring stability critical
- Alpha Lubricator: Test all quills for flow at 700 mm bore
- Crosshead bearing: High inertia and side forces at 3256 mm stroke — monitor temperature closely
- Stuffing box: 3256 mm stroke = very high relative movement — check drainage at short intervals
- Piston rod: Deflection and surface condition
- ME-B control: Sensors, EICU, actuators for function
- Camshaft: Chain elongation with long stroke
- Check SaCoSone software status
- Scavenge air box: Accessible at 700 mm — increased oil ingress risk with G-type
- Turbocharger: 1-2 TC on 6×70 — cleanliness condition
- Exhaust temperature across 6 cylinders
- Cylinder head gaskets for blow-by
- Check exhaust valve seat
- Scavenge port edges
Logbook reference values
| Parameter | Expected | Deviation means |
|---|---|---|
| Exhaust temperature by cylinder | 340–410 °C at MCR | Spread >15 °C → check electronic injection |
| Scavenge air pressure | 2.5–3.2 bar | Drop → TC/cooler |
| Pmax | ±2 bar cylinder balance | Deviation → check control system |
| Crosshead bearing temperature | 55–65 °C | Rise >5 °C → investigate immediately |
| Cylinder oil feed rate | 0.5–0.8 g/kWh | Calibrate Alpha Lubricator |
Common Failure Modes
Expert tips
- 💡 6×G70ME-B9.5 with S/B 4.65 and 3256 mm stroke: One of the most stretched engines — stuffing box care and scavenge air box inspection have the highest priority
- 💡 At 700 mm bore and G-type: Check quills at every piston withdrawal — with the extreme side force, uniform lubrication around the circumference is critical
- 💡 6 cylinders offer better vibration behavior than 5 cylinders and sufficient power for Panamax applications — a balanced configuration despite the extreme S/B
Related components
Classification & regulatory
IMO Tier II compliant. Tier III-capable with EGR/SCR. EEDI-optimized through G-type and ME-B. MARPOL Annex VI — VLSFO.
Reference content for inspector orientation. Always verify against manufacturer's manual, latest service letters and class society requirements.
Other Cylinder Configurations 23
Components & Design
Component data being added…
Technical Data
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