Cylinder Head Inspection

Reference: VALVES AND CYLINDER HEAD DISASSEMBLY AND REASSEMBLY 

• Remove all carbon deposits from combustion chambers.
  NOTE: Do not use any sharp-edged tool to scrape off carbon deposits. Be careful not to scuff or nick metal surfaces when removing carbon. The same applies to valves and valve seats, too.
  Fig 1: Identifying Carbon Deposits From Combustion Chambers

  Courtesy of SUZUKI OF AMERICA CORP.
• Check cylinder head for cracks on intake and exhaust ports, combustion chambers, and head surface.
• Using a straightedge (1) and thickness gauge (2), check flatness of cylinder block mating surface at a total of 6 locations. If distortion limit is exceeded, correct mating surface with surface plate and abrasive paper of about #400 (Waterproof silicon carbide abrasive paper): place abrasive paper on surface plate and rub mating surface against paper to grind off high spots. If distortion exceeds 0.25 mm (0.0098 in.), replace cylinder head.

  Leakage of combustion gases from this gasket joint is often due to warped mating surface: such leakage results in reduced power output.

  Distortion for cylinder head surface on piston side 

  Standard: 0 - 0.05 mm (0 - 0.0020 in.) 

  Fig 2: Checking Flatness Of Cylinder Block Mating Surface

  Courtesy of SUZUKI OF AMERICA CORP.
  Fig 3: Identifying Distortion For Cylinder Head Surface On Piston Side

  Courtesy of SUZUKI OF AMERICA CORP.
• Distortion of manifold seating faces:

  Check seating faces of cylinder head for manifolds, using straightedge and thickness gauge, in order to determine whether these faces should be corrected or cylinder head replaced.

  Distortion for cylinder head surface on intake and exhaust manifold 

  Standard: 0 - 0.05 mm (0 - 0.0020 in.) 

  Fig 4: Identifying Distortion For Cylinder Head Surface On Intake And Exhaust Manifold

  Courtesy of SUZUKI OF AMERICA CORP.