Engine piston – Hahn & Sohn HDE20SS3-DW

The piston is one of the most heavily loaded components in the engine — during every operating cycle, it transfers combustion pressure to the crankshaft and must withstand high temperatures and mechanical stress. A damaged or worn piston (e.g. a burnt piston crown or worn piston ring grooves) results in loss of compression, increased oil consumption, or engine smoke.

• Compatible with the WEICHAI WP2.3D25E200 engine (Hahn & Sohn HDE20SS3-DW generator, 20 kW / 25 kVA). The piston has a combustion chamber in the crown, three grooves for piston rings, and a piston pin bore with retaining rings.
• When replacing the piston, the piston rings must also be replaced and the condition of the cylinder bore checked — using an old worn piston ring with a new piston or vice versa would not ensure proper compression sealing.

 WHY CUSTOMERS CHOOSE IT

• Exact match for the WEICHAI WP2.3D25E200 engine
• Essential part for a complete engine overhaul

PRACTICAL TIP

When installing the piston, always follow the directional arrow stamped on the crown — it indicates the correct orientation of the piston relative to the front of the engine. A piston installed in the opposite orientation may collide with the valves or cause uneven loading.

KEY FEATURES

• Type: engine piston with combustion chamber
• 3 grooves for piston rings
• Piston pin bore
• Designed for engine: WEICHAI WP2.3D25E200
• Compatible generator: Hahn & Sohn HDE20SS3-DW (20 kW / 25 kVA)

USE / INSTALLATION / OPERATION

1. Remove the cylinder head and oil sump according to the service procedure.
2. Disconnect the connecting rod from the crankshaft and push the complete piston assembly (piston with connecting rod) upwards out of the cylinder bore.
3. Before installing the new piston, check the condition of the cylinder bore (wear, ovality) and have it rebored if necessary.
4. Fit new piston rings to the piston, observing the specified order and orientation of the rings.
5. Insert the piston into the cylinder using a suitable piston ring compressor, ensuring the correct orientation according to the directional arrow.
6. Connect the connecting rod to the crankshaft and tighten to the specified torque.

Installation requires experience with complete engine overhauls, special tools (piston ring compressor), and cylinder bore measurement — we do not recommend replacing it yourself without specialist knowledge.