5-30 ENGINE TOP END
Seat Cutter Operation Care
1. This valve seat cutter is developed to grind the valve for
repair. Therefore the cutter must not be used for other
purposes than seat repair.
2. Do not drop or shock the valve seat cutter, or the dia-
mond particles may fall off.
3. Do not fail to apply engine oil to the valve seat cutter
before grinding the seat surface. Also wash off ground
particles sticking to the cutter with washing oil.
Do not use a wire brush to remove the metal particles
from the cutter. It will take off the diamond particles.
4. Setting the valve seat cutter holder in position, operate
the cutter in one hand. Do not apply too much force to
the diamond portion.
Prior to grinding, apply engine oil to the cutter and dur-
ing the operation, wash off any ground particles sticking
to the cutter with washing oil.
5. After use, wash it with washing oil and apply thin layer
of engine oil before storing.
Marks Stamped on the Cutter
The marks stamped on the back of the cutter [A] represent
60° ........................... Cutter angle [B]
37.5 ....................... Outer diameter of cutter [C]
Clean the seat area carefully.
Coat the seat with machinist's dye.
Fit a 45° cutter into the holder and slide it into the valve
Press down lightly on the handle and turn it right or left.
Grind the seating surface only until it is smooth.
Do not grind the seat too much. Overgrinding will
reduce valve clearance by sinking the valve into the
head. If the valve sinks too far into the head, it will
be impossible to adjust the clearance, and the cylin-
der head must be replaced.