Combustion Jet Replacement - Mitsubishi S3L Service Manual

CYLINDER HEAD AND VALVE
MECHANISM
Figure 77 Lapping valve in seat
Figure 78 Removing combustion jet
64 / 195 64 / 195
Compound
Round bar
Combustion jet
7. Valve lapping
Be sure to lap the valves in the seats after refacing
or replacing the valves or valve seats.
1) Put a small amount of lapping compound on
the valve face.
NOTE
• Do not put lapping compound on the valve stem.
• Use a lapping compound of 120 to 150 mesh for
initial lapping and a compound of finer than 200
mesh for finish lapping.
• Mixing the compound with a small amount of
engine oil will help put the compound on the
valve face uniformly.
2) Using a lapping tool, hold the valve against
the seat and rotate it only a part of a turn, then
raise the valve off its seat, rotating it to a new
position. Press the valve against the seat for
another part of a turn. Repeat this operation
until the compound wears and loses its cutting
property.
3) Wash the valve and valve seat with dry
cleaning solvent.
4) Apply engine oil to the valve and lap it in the
seat.
5) Check the valve face for contact.

17.6 Combustion jet replacement

Replace the combustion jets only when they are
cracked or defective.
1. To remove the jet, insert a 6 mm (0.24 in.) diameter
round bar through the bore in the cylinder head for
the glow plug and tap around the jet.
ENGLISH
Service Manual Mitsubishi SL-Series diesel engines
INSPECTION
Version 08/2004