System oils for crosshead crankcases.
A two-stroke crosshead engine separates its cylinder lubrication from its crankcase. The system oil circulates through bearings, the crosshead guide and the cooling circuit — a very different duty from the cylinder oil above it.
SYS 30 BN 5 — Everllence No Objection Letter
NOL No. 17679-2026, issued 12 March 2026 and valid to 12 March 2031. Scope: system oil, 5 BN, SAE 30, Group 1 — for Everllence B&W two-stroke engines.
See the documentsBN 5 or BN 6?
SYS 30 BN 5
The standard choice for modern Everllence B&W and WinGD crosshead engines, and the grade carrying the current No Objection Letter.
SYS 30 BN 6
Slightly higher alkaline reserve where cylinder oil carry-over into the crankcase is a known characteristic of the installation.
Guidance only. Follow the engine builder's prevailing system oil recommendation and your condition monitoring results.
Typical properties
| Product | TBNmgKOH/g | KV 100°CcSt | KV 40°CcSt | VI | Flash°C | Pour°C | Densityg/ml |
|---|---|---|---|---|---|---|---|
| SYS 30 BN 5 | 5.0 | 11.40 | 105.9 | 94 | 246 | -18 | 0.891 |
| SYS 30 BN 6 | 6.0 | 11.50 | 106.4 | 95 | 246 | -18 | 0.893 |
Both grades SAE 30, Group 1. Performance claims: MAN and WinGD. Typical values from Sinova Group technical data sheets (Form 002-EN, 5 January 2025).