Silent generator rental

Rent Qingdao diesel generator cylinder head repair service

1. The technicians from Qingdao Generator Rental Company are to conduct a cylinder head crack inspection.

Generally, cracks are prone to occur at the cylinder block flat surface, valve guide holes, injector holes, and coolant jacket walls. Inspection can be conducted using hydrostatic testing, pneumatic testing, and magnetic particle inspection methods.

2. The technicians from Qingdao Generator Rental Company will conduct a cylinder head flatness inspection.

If the mating surface of the cylinder head and cylinder gasket shows scratches, corrosion, or uneven wear, it should be inspected. Flatness is checked using a straight edge and a feeler gauge. The cylinder sleeve is machined in increments of 0.1270 to 0.1524mm each time. The cylinder head should be scrapped when the thickness is machined to the service limit. The thickness of the Cummins 6BT series diesel engine cylinder head is 111.00mm for the smaller size and 111.25mm for the larger size, with the wear limit at 110.24mm. Note that only a 0.7939mm cylinder gasket is allowed if the cylinder head flatness has not been re-machined.

The cylinder head thickness X of the KTTA type diesel engine is not less than 119.76mm.

The top and bottom surfaces of the cylinder head must be parallel, with a non-parallelism of no more than 0.13mm; otherwise, it may cause deformation of the cylinder sleeve seat hole.

If during the air pressure test or water pressure test, the technicians from Qingdao Generator Rental Company discover any leakage or damage to the injector sleeve, the injector sleeve should be replaced.

Remove the nozzle sleeve with a puller.

2) Clean the nozzle sleeve seal surface with a steel wire brush to remove impurities.

3) If the edge of the contact surface between the cylinder head and the fuel injector sleeve is worn, it can be turned with a lathe, with the cutting depth not exceeding 0.254mm.

3. The technicians from Qingdao Generator Rental Company will perform the installation of the injector sleeve.

1) Apply a thin layer of clean engine oil to the new O-ring of the喷油器 sleeve, and install it into the O-ring groove of the cylinder head.

2) Insert the injector sleeve into the cylinder head bore using a tool, then secure it with a clamping tool. Use an expander to expand the top and bottom of the injector sleeve, ensuring a sealed fit with the cylinder head.

3) Use a nozzle holder lathe to turn the nozzle sleeve seat. Insert the nozzle into the cylinder head and tighten the bolts to 14-16 N·m. Install the nozzle clamp, then measure the distance from the bottom flat surface of the cylinder head to the top of the nozzle with a micrometer to determine the protrusion amount. The protrusion amount for the 6BT diesel engine nozzle is 1.52-1.78mm. If the protrusion amount is insufficient, turn the nozzle sleeve seat.

4) Apply blue oil to the nozzle sleeve seat surface, install the nozzle, and tighten it to the specified torque. Then remove the nozzle. The technician from Qingdao Generator Rental Company should inspect the contact condition of the seat surface; the oil mark should be a smooth circle with a minimum width of 1.52mm. If the width of the contact surface does not meet the requirements, replace the nozzle sleeve or use a cone-shaped brush to clean the nozzle seat hole. Check the seal ring mark here; if the seal is still outside the specified range, the cylinder head must be replaced or repaired.