Camshaft Bearings - Mercury MerCruiser Service Manual

b. Measure the piston diameter at the skirt 12 mm (0.472 in.) from the bottom of the skirt at a right angle to the piston
pin bore.
b
c. Subtract the piston diameter from the cylinder bore diameter to determine piston to bore clearance.
d. Determine if the piston to bore clearance is in an acceptable range.
Description
Production piston to bore clearance
2. If a used piston is not satisfactory, determine if a new piston can be selected to fit the cylinder bore within the specified
range.
3. If the cylinder bore must be reconditioned, measure the new piston diameter, then hone the cylinder bore to the correct
clearance.
4. Mark each piston to identify the cylinder for which it was fitted.

Camshaft Bearings

Camshaft Bearing Installation
IMPORTANT: When installing the camshaft bearings, always look to ensure that the camshaft bearing lubrication hole is
located at the 3 o'clock position. The proper positioning of the camshaft bearing lubrication hole is to ensure the best lubrication
of the engine camshaft journals.
1. Select the handle (10), the expanding driver (4–8), the washer (2 or 3), and the expander assembly (15) from the J33049.
90-8M0099748 eng DECEMBER 2015
a
a - Piston diameter
b - Measurement location
22022
0.055–0.083 mm (0.0022–0.0032 in.)
a
a - 3 o'clock position
59531
© 2016 Mercury Marine
Engine Inspection and Assembly
6.2 Liter (377 cid)
Page 3B-9