The high-pressure hose connecting the two hydraulic cylinders is positioned forward, closely hugging the crankshaft gear near the ninth main bearing. This setup poses several safety risks, such as the potential for misalignment or bending in an unsafe direction, which can obstruct the operator's view and lead to operational hazards. In one instance, this issue resulted in the failure of the main bearing tensioner. After a thorough analysis and by incorporating feedback from on-site operators, the design was modified. The lower part of the cylinder was raised, while the height of the cap hole on the cylinder was reduced. This allowed the high-pressure hose to be replaced with a rigid straight tube, which was then properly installed with a safety shield. During testing of the prototype for the cylinder head bolt tensioner, the four hydraulic cylinders were connected in the hydraulic system. However, during operation, it was observed that after the system was unloaded, the fourth hydraulic cylinder (associated with the oil-cooled electric drum) experienced an unexpected explosion. Further investigation revealed that the piston movement in this cylinder was significantly less compared to the other three. It was determined that the cylinder was not returning properly. To ensure synchronization among all four cylinders, increase the piston stroke, reduce manual effort, and improve overall efficiency, the system was re-evaluated. Proper oil pipe diameter and joint size were selected based on these findings. A series of comparative experiments were conducted under the same test conditions, using different types of high-pressure hoses, rigid pipes, and various diameters. The results showed that rigid pipes provided the best performance. Additionally, during use, it was noted that the lever included in the accessory set for tightening nuts had a short service life. This was due to oil contamination and sand buildup between the nut and screw during disassembly, making the lever difficult to operate. The original material of the lever was too hard, leading to breakage, while softer materials caused deformation. As a result, the lever eventually failed on the diesel engine. Although the valve stem was improved, its service life remained unsatisfactory. This issue requires further attention and resolution to ensure long-term reliability and safety. Single Eyelet,Eyelets Prym,Prym Grommets,Washer Eyelet NINGBO ZONGLAN MECHANICAL AND ELECTRICAL EQUIPMENT MANUFACTURE CO., LTD , https://www.zonglaneyelet.com