Exhaust valve – Hahn & Sohn HDE20SS3-DW

The exhaust valve is one of the most thermally and mechanically stressed components in the engine — during operation, it repeatedly opens and closes the path for exhaust gases from the combustion chamber and must reliably withstand high temperatures and pressure shocks when seating against the valve seat. A worn or damaged exhaust valve can cause loss of compression, uneven engine operation, or leakage of exhaust gases.

• The valve is designed for the four-cylinder diesel engine WEICHAI WP2.3D25E200 (Hahn & Sohn HDE20SS3-DW generator, 20 kW / 25 kVA). The stem has a groove for the retaining clip, which secures the valve spring retainer.
• During a complete cylinder head overhaul, the exhaust valves are usually replaced as a complete set for all cylinders at the same time, even if wear is uneven — this ensures uniform seating and smooth engine operation after repair.

WHY CUSTOMERS CHOOSE IT

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

PRACTICAL TIP

When replacing exhaust valves, always check the condition of the valve seats in the cylinder head as well — if the seats are burnt or uneven, even a new valve will not seal reliably and the seats must first be repaired (reground or replaced).

KEY FEATURES

• Type: exhaust valve (poppet valve)
• Groove on the stem for the valve spring retaining clip
• 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 valve train according to the service procedure.
2. Compress the valve spring using a suitable spring compressor, remove the retaining clip, and remove the old valve.
3. Check the condition of the valve guide and valve seat in the cylinder head.
4. Insert the new valve into the guide, install the spring with the retainer, and secure it with the retaining clip.
5. After reinstalling the cylinder head, adjust the valve clearances to the specified values.

Installation requires experience with valve train servicing, suitable tools (spring compressor), and valve clearance measurement — we do not recommend replacing the part yourself without specialist knowledge.