PUMP GP-PISTON 9T9350 - Caterpillar

Length of a Connecting Rod
CRL is the length of the connecting rod. Refer to Table 1 for each grade of length of connecting rod.In order to ensure that the piston height above the cylinder block is correct, six grades of length of connecting rods are used. The grade of length is identified by a letter or a color which is marked on the side of the connecting rod. The longest grade is marked with the letter "F". The shortest grade is marked with the letter "L". The difference in length between each grade of connecting rods is 0.046 mm (0.0018 inch).The grade of length of a connecting rod is determined in the factory by machining an eccentric hole in a semi-finished piston pin bushing. Therefore, the grade of length is determined by the position of the center of the hole in the piston pin bearing. There is a hole that is in the connecting rod for the piston pin bearing. The grade of length is not determined by the position of the hole that is in the connecting rod for the piston pin bearing.If the connecting rod must be replaced, a new connecting rod assembly must be purchased and installed. Refer to Table 1 for more information.A new piston pin bearing is installed in the new connecting rod at the factory. The bore of the piston pin bearing is reamed to the correct eccentricity.Piston Pin Bearings
Note: This procedure requires personnel with the correct training and the use of specialized equipment for machining.If the piston pin bearing requires replacement but the original connecting rod is not replaced, the following procedures must be performed:
Determine the grade of length of the connecting rod. Use one of the following characteristics:
The mark
The color
Measuring the lengthThe length of the connecting rod is measured when the following items are completed:
Remove the bearing for the crankshaft journal.
Install the original piston pin bearing in the connecting rod.For more information, refer to "Measure the Length of a Connecting Rod" in this Module.
Ensure that the connecting rod is aligned parallel and that the connecting rod is not distorted. Refer to "Distortion of a Connecting Rod" in this module.
Remove the piston pin bearing from the connecting rod. Install a new piston pin bearing in the connecting rod. The new piston pin bearing is partially finished. The new piston pin bearing must be bored off-center to the correct diameter. This off-center position is determined by the grade of length of the connecting rod. Refer to Table 1. The correct diameter of the bore in the piston pin bearing is found in the Specifications Module, "Connecting Rod" topic. Surface finish of the bored hole in the piston pin bearing ... Ra 0.8 micrometers
Machine the ends of the piston pin to the correct length. Remove any sharp edges. Refer to the Specifications Module, "Connecting Rod" topic for more information.
If the grade of length of the connecting rod is changed, the