With decades of proven experience in Four stroke engines, KIMI has continually invested in state-of-the-art equipment and skilled personnel to develop an advanced production line tailored to meet the most stringent OEM specifications for 4 stroke marine heads of multi-Brands like MTU, WARTSILA, YANMAR, DAIHATSU, MAN. Standard Overhauling process of four stroke cylinder covers is designed to extend service life and enhance durability, guaranteeing optimal performance during engine operation.

On four stroke Cylinder Heads, cavitation or corrosion in the exhaust valve seat bore is a common issue. Machining the pocket to oversize is usually the most cost-effective solution for dealing with exhaust valve seat bore issues. However, reconditioning process can differ a lot from vendor to vendor.

Our Standard Overhauling of Four stroke Cylinder heads includes:

  • Specialized cleaning technique, powered by the latest technology, ensuring superior cleanliness of hard-to-reach areas on cylinder heads
  • Inspection measurements by Certified Personnel, including thorough spring elongation check
  • Renewal of cylinder cover seats, valves, valve guides, injector sleeve
  • High Precision Grinding Technology for seats and valves, guaranteeing tighter tolerances and perfect sealing between marine head seats and valves
  • Machining of seat pockets to an oversize dimension through Next generation Precision Grinding CNC machine
  • Grinding of cover in the way of the liner landing surface
  • Pressure Testing
  • Coating

KIMI’s Next Generation Precision Grinding CNC machine sets new quality standards for four stroke cylinder heads overhaul and seat pockets reconditioning. Advantages include:

  • Grinding capability in seat diameter ranging from 13–250mm
  • Guaranteed Grinding Seat Circularity < 0.003mm even on seats as large as 200mm in diameter
  • Superior Surface finishes compared to traditional methods. Surface Roughness ≤4Ra
  • NoChatter Marks or Undulations even for the most complex shapes of valves’ Seats
  • Perfect seal between Valve and Seat. Long lasting air tightness of valve seats, resulting in significantly increased performance of cylinder head
  • Unparalleled speed of execution reaching one minute to machine a seat bore

In the event of excessively corroded seat pockets or cooling grooves of marine heads, KIMI also provides the option of Reconditioning by laser cladding using anticorrosive alloys and machine to standard dimensions, achieving a full metallurgical bond of filler powder with the base material. Both seat pockets and cooling grooves of marine heads are fully restored back to nominal size.