DS 19 OPERATION No. DS 100-3 : Overhauling an engine 49
21 Clean the parts. Do not wash the crankshaft bearing in order to avoid removing the grease. TOOLS
The bearing should be packed with new grease.
22 With a spray gun paint the inside of the crankcase. Use a paint resisting the action of hot oil (paint such as
AC.8, sold by CLEMENT and RIVIERE or MOUQUET).
ASSEMBLY (see Pl. 1)
23 To prepare the cylinder head (see Pl. 4)
a) Grinding the cylinder head:-
A deviation of 0.05 mm in the truth of the surface is admissible.
A slight grinding on the surface is possible. The original thickness of the cylinder head must not be reduced
by more than .3 mm.
If it is suspected that the cylinder head has been ground, check the dimension “c” (see fig. 6).
This dimension should be “c” = 26.5 +0.1/-0.2 mm.
b) Grinding the valves (Black and Decker type valve grinder).
NOTE – The angle of the exhaust valve face is 90˚.
The angle of the inlet valve face is 120˚.
There should be a radius of approximately 0.5 mm on the corners of the valve heads (at “a” and “b”. see fig. 3).
c) Grinding the valve seats.
NOTE – the width “l” of the seat must be between 0.9 and 1.5 mm. Use the following grinding wheels to
obtain these dimensions:-
Inlet valve seat:
For the seating . . . . . . . . . . . . . . 120˚ biconical wheel . . . . . . . . . . . . . . 1662-T
For the top clearance . . . . . . . . . . . . . . 150˚ biconical wheel . . . . . . . . . . . . . . 1630-T
For the lower clearance . . . . . . . . . . . . . 90˚ biconical wheel . . . . . . . . . . . . . . 1630-T
Exhaust valve seat
For the seating . . . . . . . . . . . . . . . . . . . 90˚ biconical wheel . . . . . . . . . . . . . . 1627-T
For the top clearance . . . . . . . . . . . . . . 150˚ biconical wheel . . . . . . . . . . . . . . 1627-T
For the lower clearance . . . . . . . . . . . . 60˚ wheel . . . . . . . . . . . . . . . . . . . . . . 1633-T
The large diameter of the seating must be equal to the largest diameter of the valve (see fig. 1 and 2) . . . . . . Grinding wheels
16 62-T, 1630-T,
1627-T and 1633-T
d) Grind the valves (suction tool 1615-T, see fig.4) driven by an electric, pneumatic or hand operated grinder Suction valve
grinder 1615-T
To Next Page
Loading...
