Bergen KVG piston 250 mm, G1/G2 (4 rings)

Loose spare piston for Bergen KVG / KVGS lean burn gas engines, 250 mm bore. This is the earlier piston type with four ring grooves (three compression rings and one oil scraper ring), used before the G3/G4 upgrade. G3 and G4 pistons have three rings.

The G4 piston is the updated version of the earlier pistons and can also be used in G1, G2 and G3 engines, with the G4 piston ring set (3 rings). G4 pistons from the same engine are also available: Bergen KVG G4 piston 250 mm.

Supplied without piston rings and gudgeon pin.

Piston ring combination for the aluminium alloy piston, Bergen K-G gas engine (Bergen drawing L 566/95, May 1991):

• 1. Compression ring, chromium plated, asymmetric barrel shaped – part no. 700683
• 2. Compression ring (minute ring), chromium plated – part no. 700267
• 3. Compression ring (minute ring) – part no. 017687
• 4. Oil control ring, chromium plated, with garter spring – part no. 024625

Rings 1–3 have a «TOP» marking that must point upwards.

We also have Bergen piston ring set 422943 (4 rings, 250 mm, K / L / R series). It contains ring 700683 and different part numbers for the other rings (704837, 704836, 017689), possibly later replacements. Check that the rings match the grooves before fitting.

From the spare part stock of a Bergen KVGS-12 lean burn biogas engine. The piston was left over from before the engine was upgraded to G4 by Rolls-Royce in 2009.