Engine Inspection And Repair; Checking The Cylinder Head - Westerbeke 9.0 BCG Technical Manual

ENGINE INSPECTION AND REPAIR
NOTE: Before washing the cylinder head and block, check them for indications of water leaks,
gas leaks, damage or cracks. After checking these components, wash each part to remove
any adhered matter such as pieces of gasket, dust, oil, carbon, and scale. Since the cylinder
head, cylinder head cover, timing chain cover and other engine parts are made of aluminum,
handle them carefully to ensure against damage. Do not use cleaning solutions that will be
harmful to the aluminum.
Checking the Cylinder Head
1. Replace the cylinder head if it shows signs of water leaks, gas leaks or cracks.
2. Measure the extent of warping (flatness) on the lower surface that mates with the cylinder block. If the
warping exceeds the allowable limit of distortion, grind the surface to within the specified grinding
tolerance. If the warping exceeds the allowable grinding tolerance, then replace the cylinder head.
Specified Cylinder Head Height:
Allowable Limit of Distortion:
Grinding Tolerance:
Westerbeke Generators
BCG4.0KW
4.953 inches (125.8 mm)
BCG 6.5KW and BTG 9.0KW
4.953 inches (125.8 mm)
BCG4.0KW
0.002 inches (0.05 mm)
BCG 6.5KW and BTG 9.0KW
0.0039 inches (0.10 mm)
BCG4.0KW
0.0118 inches (0.30 mm)
BCG 6.5KW and BTG 9.0KW
0.0118 inches (0.30 mm)
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