Inspection Of Valves; Inspection Of Valve Springs; Valves Sealing Lest - MOTO GUZZI V-7 700 Operating Handbook

INSPECTION OF VALVES
Check valves integrity and existing lash between
stem and guide (for clearance refer to coupling
data chart and Fig. 20) . To regrind valves, insert
valve stem In self-centering chuck of Universal
Grinder (see Fig . 21) and adjust chuck swivel
table so that valve will have an angle of inclina-
tion as follows:
- exhaust valve: 4S
e
25'
+
1~'
- inlet valve :
SOU 25'
o
+
15'
After grinding check thickness of valve head at
max. dia. to be not Jess than 0.8 mm. (.0315") .
Should surface at stem end show any defor-
mation. regrind same on grinding wheel (see
Fig. 22).
18
Whenever regrinding valve seats, it is advisable
to check that valve springs are compressed bet-
ween
37
mm. and 38 mm . (1.456 - 1.496"). Adjust
by adopting suitable washers at bottom collar,
between spring and cyli nder head .
INSPECTION OF VALVE SPRINGS
Check that valve springs are not c racked and
have not lost their elasticity.
Spring , compressed at 37 mm . (1.456"), must
o
show a load of Kg . 33
+
2 (72 Ibs - 12 ozsl
(closed valve position).
Spring, compressed at 28 mm. (1 .024"), must
o
show a load of Kg . 60
+
2 (132 Ibs - 4 ozs)
(open valve position).
Springs flexibility can be checked by suitable
apparatus (see Fig . 23). As to load and deforma-
tion data refer to Fig . 24.
VALVE SEALING TEST
After reassembling valves on cylinder head , fill
up inlet and exhaust ducts with gasoline. Losses.
if any, will be detected by liquid leaking in com-
bustion chamber.
Fig. 23