848747 Volvo.Penta Screw

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 letter that is stamped on the connecting rod must be removed. Etch a letter that is for the new grade of length on the side of the connecting rod. Note: Do not stamp a new letter on the connecting rod. The force of stamping could damage the connecting rod.Table 1 references the following information: grade of length of the connecting rod, color of the mark and lengths of the connecting rods
Table 1
Grade of Length Color Length Of The Connecting Rod (CRL)
"F" Red 165.728 to 165.761 mm (6.5247 to 6.5265 inch)
"G" Orange 165.682 to 165.715 mm (6.5229 to 6.5247 inch)
"H" White 165.637 to 165.670 mm (6.5211 to 6.5229 inch)
"J" Green 165.591 to 165.624 mm (6.5193 to 6.5211 inch)
"K" Purple 165.545 to 165.578 mm (6.5175 to 6.5193 inch)
"L" Blue 165.499 to 165.532 mm (6.5157 to 6.5175 inch) Measure the Length of a Connecting Rod
If the mark or the color of the grade of length cannot be observed on the connecting rod, perform the following procedure:
Illustration 1 g00326546
Measure the length of the connecting rod.
(1) Measuring pins
(2) Connecting rod
(CRL) Connecting Rod Length
Refer to Illustration 1. Use the following tools in order to measure the length of the connecting rod:
Appropriate gauges for measuring distance
Measuring pins (1)
Ensure that measuring pins (1) are parallel. "CRL" is measured when the bearing for the crankshaft journal is removed and the original piston pin bearing is installed. Measure "CRL". Compare the "CRL" that is measured to the "CRL" that is listed in Table 1. The grade of length of the connecting rod is determined by the "CRL". Refer to Table 1 for the correct grade of length.Distortion of a Connecting Rod
Use the following tools in order to measure the distances for connecting rod (2) that are specified in Illustration 2:
Appropriate gauges for measuring distance
Measuring pins (1)
Illustration 2 g00326423
Measure the connecting rod for distortion.
(1) Measuring pins
(2) Connecting rod
(L) The length between the center of the piston pin bearing and the center of the bearing for the crankshaft journal
Measure the connecting rod for distortion and parallel alignment between the bores. The bores for the crankshaft bearing and the bearing for the piston pin must be square and parallel with each other within the required limits. If the piston pin bearing is removed, the limit "L" is the following value: 0.25 mm ( 0.010 inch)The limits are measured at a distance of 127 mm (5.0 inch) from each side of the connecting rod.If the piston pin bearing is not removed, limit "L" should be the following value: 0.06 mm ( 0.0024 inch)"L" is equal to 219.08 0.03 mm (8.625 0.001 inch).
Inspect the piston pin bearing and the piston pin for wear or damage.
Measure the clearance of the piston pin in the pis