A precision-manufactured engine piston, a key component in repair kits for Perkins AR engines. Unlike many other Perkins engines (e.g., AA/AB), this AR model features a nominal bore diameter of 103 mm. The piston is the heart of the power unit, responsible for transferring energy from the combusted mixture to the crankshaft. Made from a high-grade aluminum alloy, it ensures optimal thermal expansion and durability.
GX-AFTER is the smart choice for your machine. We provide high-class replacement parts that combine excellent quality with an attractive price. Each part is carefully verified to ensure full compatibility and reliability you can depend on.
| Brand | Type / Series / Model |
|---|---|
| JCB | Backhoe Loaders: 2CX, 2DX, 3CX, 4CX Telehandlers (Loadall) Wheel Loaders Skid Steer Loaders (ROBOT) Rough Terrain Forklifts (RTFL) |
The list above is for reference. Fitment is dependent on the Perkins AR (103mm) engine model.
An engine overhaul is a complex process. Piston installation must be done in sterile conditions. Any contamination (dirt, metal shavings) entering the cylinder will immediately score the liner and destroy the engine. Always check piston ring end gaps and piston installation direction.
The piston hermetically seals the cylinder (with piston rings) and transfers the immense force of combustion to the connecting rod. It is one of the most stressed components in the engine. Its failure necessitates a major overhaul.
📞 Can't find the part you're looking for?
No problem. Our website shows only a few thousand of the over 60,000 parts we have in stock. Contact us – we probably have what you need on the shelf!
Bore Size is a fundamental engine parameter. 103mm pistons (like this one, for the AR engine) and 100mm pistons (for AA/AB/AK engines) are in no way interchangeable. Installing a 100mm piston in a 103mm cylinder will cause an immediate loss of compression, and a 103mm piston will not physically fit in a 100mm cylinder.
2. How do I know if I need a nominal or oversize piston?This piston is a nominal size (103 mm). Before purchasing, a mechanic must measure the cylinder bore with a bore gauge. If the cylinder is worn but within tolerance, it can be honed for this piston. If the wear is too great, the cylinder must be "bored" (re-bored) and an oversize piston (e.g., +0.50 mm) must be used.
3. What are valve seat depths (1.2/1.5 mm)?These are special cut-outs in the piston crown that create "pockets" for the opening intake and exhaust valves. This ensures a safe clearance between the piston at its top dead center and the valves, preventing a collision. The different depths (1.2mm and 1.5mm) are typical for intake and exhaust valves which have different lift heights.
Have doubts or need confirmation to avoid costly downtime? Call us. Our experts will help you choose the right part to get your equipment back to work as soon as possible.
Data sheet
Specific References
Manufacturer
Responsible person
See also similar products





Engine piston suitable for, among others: for JCB 2CX 3CX 4CX, front loaders and telehandlers with naturally aspirated AR engine.

















