Mercury 15 EFI FourStroke, Service Manual

Page: 169 / 406

9. Remove the bolts and the crankcase cover.
10. Measure the gauging plastic at its maximum compressed width.
a - Compressed gauging plastic
b - Gauging plastic scale
11. If the oil clearance is out of specification limit, measure the inside diameter of the cylinder block and crankcase cover main
bearing journals.
Selecting New Main Bearings
1. Locate the main bearing code on the cylinder block.
2. The journal size of the cylinder block is stamped with a code letter on the upper end of the cylinder block.
NOTE: The identification code for the upper main bearing is
A, B
.
The identification code for the lower main bearing is
X, Y
.
B Y
B Y
64071
3. Use the color coded main bearing that matches the main bearing code letters on the cylinder block.
3147
Bearing Code Bearing Color Bearing Size Bearing Thickness
A, X Blue 39.0–39.008 mm (1.5354–1.5357 in.) 1.488–1.494 mm (0.0586–0.0588 in.)
B, Y Red 39.008–39.016 mm (1.5357–1.5361 in.) 1.494–1.500 mm 0.0588–0.0591 in.)
a
b
11637
Cylinder Block/Crankcase
Page 4A-22 © 2018 Mercury Marine 90-8M0125265 eng NOVEMBER 2017