4TN78 4TN78T Overhaul Re-ring Kit. Fits for Yanmar 4TN78 4TN78T 4TN78T-RJ Engine. Fits for John Deere JD50 50 Excavator. Package included: STD Engine Overhaul Re-ring Kit. 1 Set Full Gasket Kit with Head Gasket. 4 Sets STD Piston Rings. 1 Set STD Crankshaft / Main Bearing. If you need + 0.25mm + 0.5mm or another size. 1 Set STD Connecting Con Rod Bearing. 1 Set STD Thrust Washer / Bearing. If you are not sure whether it is suitable for your engine, please provide your engine nameplate or part number, and we will help you confirm. If you have any questions or need other sizes, you can let us know. If there is no external requirement, we will send STD size, thank you.