Yuchai YC4D Engine Parts: Identification, Wear Items and Part Numbers

Published 2026-09-14 · Yuchai engine parts · EPID

The Yuchai YC4D is one of the engine families we supply most often. This guide covers what the engine is used for, how to identify your variant, which parts wear first, and how to order by OEM part number without guessing.

What the Yuchai YC4D is used for

The YC4D family powers medium trucks, forklifts and small gensets. Yuchai engines dominate buses and mid-size construction equipment, and demand has grown quickly in Russia and Vietnam. Because these engines work long hours in dusty or hot conditions, the wear parts - cylinder kits, bearings and sealing - are replaced on a schedule rather than when they fail.

We ship Yuchai YC4D parts to Southeast Asia, Russia, Africa and South America, usually for fleets, engine rebuilders and generator service companies. Most orders combine several component groups in one shipment, which is why quoting by part number matters: it is the only way to be sure two suppliers are quoting the same part.

How to identify your YC4D variant

Two Yuchai YC4D engines of the same nominal model can use different pistons, liners or head gaskets depending on build year and rating. Before ordering, take three pieces of information from the engine:

1. The engine plate. Model, serial number and power rating are stamped on the plate; photograph it.
2. The OEM number on the old part. Even a worn part carries the number, usually on the casting or a machined face.
3. The application. A YC4D in a generator set is often rated differently from the same engine in a truck, and the cooling and fuel components differ.

If you only have the serial number, send it to us - we identify the correct numbers from the parts list and confirm before you pay.

Parts that wear first on YC4D engines

YC4D part numbers and cross reference

Buyers increasingly search by number rather than by description, and for good reason: YC4D parts are shared across several ratings and the number is the only unambiguous identifier. Our Yuchai directory lists the numbers we publish, each linked to photos and specifications.

See the full list: Yuchai part numbers (20) or search all brands in the OEM part number directory.

Ordering checklist for YC4D parts

1. Engine model and serial number (photo of the plate is ideal)
2. OEM part number of the worn part, or clear photos with dimensions
3. Quantity - single pieces and sample orders are welcome
4. Quality grade: genuine, OEM-grade or aftermarket
5. Destination port or airport so we can quote FOB, CIF or DDP

Related pages

• Yuchai engine parts by category
• Yuchai part numbers list
• Diesel engine overhaul kits
• Inframe kit vs overhaul kit
• Yuchai pistons and piston rings
• Yuchai cylinder liner
• Yuchai cylinder head
• Yuchai crankshaft

Frequently asked questions