Checking The Piston Pins; Checking The Connecting Rod Bearings - Westerbeke 7.0 KW BGC -60Hz Technical Manual

Checking the Piston Pins
1. Check each piston pin's oil clearance.
A. Measure each piston pin's bore diameter.
Standard Bore Diameter:
4.5 KWBCG
Standard Bore Diameter:
7.0 KW BCG & BCGA
0.6299 - 0.6302 in.
(15.999 - 16.008 mm)
0.7086 - 0.7090
(17.999 -18.008 mm)
B. Measure each piston pin's diameter.
Standard Pin Diameter: 0.6296 - 0.6299 in.
4.5 KW BCG (15.991 -16.000 mm)
Standard Pin Diameter: 0.7083 - 0.7087 in.
7.0 KW BCG & BCGA (17.991 - 18.000 mm)
Standard Oil Clearance: 0.0002 - 0.0004 in.
(0.005 - 0.011 mm)
2. Replace the piston and piston pin if the pin's oil clearance exceeds the allowable limit specified below.
Allowable Limit: 0.0020 in. (0.050 mm)
Checking the Connecting Rod Bearings
1. Check each connecting rod bearing carefully and replace it if it is worn, scored or flaked.
2. Check each connecting rod bearing's oil clearance with a "plastigauge." If the clearance for these bearings
exceed the allowable limit, replace all the connecting rod bearings. If the connecting rod journals are
scored or flaked, grind the crankshaft's connecting rod journals and install an undersize bearing.
Bearing Oil Clearance:
Specified Limit: 0.0008 - 0.0017 in.
(0.020 - 0.044 mm)
Allowable Limit: 0.0028 in. (0.07 mm)
Kinds of Connecting Rod Bearings:
Standard
Undersize 0.0098 in. (0.25 mm)
Undersize 0.0197 in. (0.50 mm)
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