Oil Leakage Between Gearbox And Engine Unit; Rear Suspension; Oil Leakage From The Rear Wheel Drive - MOTO GUZZI 850 T3 Workshop Manual

OIL LEAKAGE BETWEEN GEARBOX AND ENGINE UNIT
To detect oil leakages between gearbox and
engine unit proceed as follows :
- first ascertain
if
the oil leaking outside comes
from the gearbox or from the engine unit; this
is quite easy to do by smelling the oil itself.
As a matter of facl the oil coming from the
gearbox smells bad and Is more viscous (if
this checking Is done (cold-group) while the oil
coming from the engine unit is less viscous
and does not smell;
-
if the oi l comes from the gearbox , the lea-
kage may be caused by the following :
1 Poor sealing between clutch pressure plate
rod (14085700) and intermediate tube (12085901)
in clutch shaft; see jf the rod is very oily and
slides freely into the clutch shaft (10 ensure a
proper sealing, the rod must force on the tube
and this must force on the clutch shaft) . In this
case, it is advisable to check that the clutch
plates are not oily.
2
Poor sealing of the ring
(90403547)
mounted
on the gearbox, flywheel side : check ring resi·
lience and wear, see if there is an oil drop
under the ring itself. Should It be worn·out,
check the surface of the clutch inner body
contacting the ring in question. This surface
must not be rough and must not show any
crush or score.
3
If the clutch inner body
(14081811)
contains
oil inside (where is locked the nut with washer
securing the clutch inner body to the clutch
shaft) ; check if the two sealing rings on clutch
inner body and clutch shaft
(90706235
and
90706235) have not lost resilience and efficiency.
4
Porosity in the gearbox; to check this, ope·
rate as follows: set the gearbox on a bench,
the clutch housing side upwards (see Pict. 123);
fill the clutch housing side with water and blow
compressed air at 4 Kp / sqcm through the brea·
ther tube"
B"
(Pict. 123).
In case of casting porosity, small bubbles will
be visible in the water. Seal the porosity by
means of latex or special plasters (Araldite
or Devcon).
If the clutch slides because of oil leakages
between engine unit and gearbox and the oil
passes between the clutch pressure plate rod
and the intermediate tube and it is ascertained
th at the oil comes out from the engine crank·
case, this may be caused by the following :
5 Oil leaking through the seal ring mounted
on the crankcase flange, flywheel side; check
ring resilience and wear, if worn·oul inspect
the crankshaft surface contacting the ring itself.
Th is surface must be perfectly smooth.
6
Eventual porosity in the engine crankcase ;
for this checking set the engine on a bench.
the flywheel side upwards, .. see Pict. 122 . (re-
move first the flywheel from the engine unit)
and fill it with water, blow compressed air at
7 Kpsqcm through the breather tube "A,. (Pict.
122).
In case of casting porosity, small bubbles
will be visible in the water. Seal the porosity
by means of latex or special plasters (Araldlte
or Devcon).
7
If the bands securing the rubber tubes of
the engine oil breather are slackened, the oil
may flow between the rubber and the metal
tubes going between gearbox and engine unit.
8 See if the two lower bolts securing the flan-
ge, flywheel side,
(12011400)
to the engine
crankcase are dry; should they be oily, set so-
me "Teflon . tape on the bolt thread.
9 See that the lower stud bolt securing the
gearbox to the engine unit Is not ally where
the reference bushing is located (left side);
otherwise set some .. Teflon,. tape on the stud
bolt thread.
OIL LEAKAGE FROM THE REAR WHEEL DRIVE
For this checking, operate as follows:
- fit the
1001
" C,. (Plct. 124) on the drive box
(this tool can be obtained from a used rear fork
right arm by welding a plate with a valve, tyre
Inn er tube type, on the arm top);
- set the drive box Into a small basin filled
with water and blow compressed air through
the valve of the tool -C. (Pict. 124) at 4 kp/ sqcm.
In case of casting porOSity, small bubbles will
be visible in the water. Seal the porosity by
means of latex or special plasters (Araldite or
Devcon).
Check also that there Is no oil leaking between
the drive box and the lower pin securing the
rear lark. Should this pin be oily, set some
• T eflon» tape on the pin thread.
N. See pages 28-29 for pictures.
REAR SUSPENSION
The rear suspension of this model can fit two
different types of shock absorber springs.
The former with 5 pOSitions. adjustable by means
of an incorporated lever.
The latter with 3 positions, ad justable by means
of
a
wrench delivered with the tool kit.
92
Springs data
Free length:
Under kg 61
load :
Under kg
122
load:
Und er kg 235 load:
mm 270
mm 230
mm190
mm 116