Wear Resistant Cast Iron Sealing Rings Oil Seal For Isuzu C240 4R Diesel Engine Overhaul

This piston ring set 5-12181-027-0 is specially developed for the Isuzu C240 (4R) 4-cylinder diesel engine. It is a standard replacement kit for forklift and small construction machine engine overhauls. The set follows OEM specifications for end gap, side clearance, and back clearance, perfectly matching STD pistons and cylinder liners.

As the core sealing component, piston rings perform gas sealing, oil control, and heat transfer — directly affecting cylinder pressure, oil consumption, and power stability. This ring set is optimized across five key aspects: base material, surface hardening, end gap precision, tension control, and sorting inspection, making it suitable for the frequent heavy-duty cycles of warehouse and site forklifts.

• Tough Ductile Iron Base — Anti-Fatigue & Anti-Breakage

  High-toughness ductile iron is adopted, offering superior fatigue strength compared to grey cast iron. It resists cracking and chipping under engine knocking and thermal cycling. This makes it reliable for forklifts with frequent start-stop and variable load conditions, preventing catastrophic damage such as ring breakage and cylinder scuffing.

• Chrome-Plated Compression Rings for Extended Wear Life

  The working face of the compression rings is coated with a dense hard chrome layer, providing high hardness and low friction loss. Under high temperature and carbon buildup inside the cylinder, the wear rate remains slow. It maintains a stable end gap and slows cylinder pressure decay, preventing power loss and hard starting after long running hours.

• Balanced Oil Ring Tension for Reliable Oil Control

  The oil ring is assembled with an expander spring for uniform circumferential tension against the cylinder wall. It scrapes excess lubricant to stop oil blow-by and blue smoke, while retaining the essential oil film to avoid dry friction. This balances oil control and lubrication, solving common oil burning issues after overhaul.

• Individually Ground End Gap for Precise Fitting

  Each ring is individually machined to reach the specified end gap according to OEM standard. Consistent gap within one set avoids gas leakage from an oversize gap or ring seizure caused by insufficient gap during thermal expansion, bringing better assembly tolerance for technicians.

• Pre-Matched Set & Batch Sampling Inspection for Consistent Quality

  All rings are sorted and matched as complete sets to prevent mixing wrong parts. Hardness, end gap, and spring tension are sampled per batch to reject defective items with bad coating or abnormal tension. The low return rate makes this set ideal for export stock and repair shop inventory.

We supply ready-stock ring sets, as well as full kits with piston, pin, and circlips for regular C240 (4R) engine overhauls.