Mercury Mariner 4 and 5HP 4-Stroke Outboards Service Shop Manual 1999, Page 7Get this manual
SPECIFICATIONS -
Piston Type .0at Skirt Standard Oversize-0.020 in(0.50 mm)
Piston to Cylinder Clearance Piston Clearance Limit Ring End Gap (Installed) Top Middle Bottom (Oil Ring) Side Clearance: Top Middle Bottom (Oil Ring) Compression Ratio With Decompression Without Decompression (Exhaust Rocker Removed) Outer Diameter Diameter of Piston Pin Hole Clearance between Piston Pin and Piston Pin Hole
Aluminum
2.321 in(58.960 mm) 2.341 in(59.460 mm) 0.001 in- 0.002 in(0.020 mm 0.055 mm) 0.006 in(0.15 mm) 0.0060.014 in(0.150.35 mm) 0.0120.020 in(0.300.50 mm) 0.0080.016 in(0.200.40 mm) 0.00150.003 in(0.040.08 mm) 0.00120.003 in(0.030.07 mm) 0.00040.007 in(0.010.18 mm) 8.5: 42 psi 14 psi (0.29 0.1 MPa) 113psi 14psi(0.78 0.1 MPa) 0.6299 in(16.00 mm) 0.6300 in(16.002 mm) 0.00010.0005 in(0.002 mm0.012 mm) 0.0020.003 in(0.0530.079 mm) 0.008 in- 0.016 in(0.20 mm0.40 mm) 0.6303 in(16.01 mm) Less than 0.002 in(0.05 mm) 1.1791.177 in(29.9429.91 mm) 0.9830.982in(24.9824.96 mm)