186
10.11.4
Checking the Crankcase Halves
-
Before proceeding to check the crankcase
halves, thoroughly clean all the surfaces and oil
ducts.
-
On the transmission side crankcase half, take
particular care cleaning the housing and oil
ducts for the following components: the oil
pump, the oil blow-by valve, the main bearings
and the cooling jet on the transmission side, see
picture.
Note:
The cooling jet is fed via the main bearings.
When working correctly, it improves the cooling of
the crown of the piston. Blockage of this jet will
increase piston temperature and the ensuing
damage would require major repairs. A missing or
unseated cooling jet can cause a serious reduction
in the oil pressure lubricating the main bearing and
connecting rod.
As mentioned in the "Lubric ation" chapter, it is
essential that the by-pass housing shows no signs
of wear capable of affecting the seal of the
lubrication pressure adjusting piston.
-
On the flywheel side crankcase half, take
particular care in cleaning the oil ducts for the
main bearings, the oil duct for the jet that
lubricates the cylinder head and the oil drainage
duct at the flywheel side oil seal.
Note:
The oil duct for lubrication of the cylinder
head is fitted with a vaporizer jet that provides so-
called 'low pressure lubrication', designed to keep
the oil temperature in the sump at an acceptable
level. Blockage of this jet will prevent proper
lubrication of the cylinder head and timing
components. A missing or unseated jet can cause a
serious reduction in the oil pressure lubricating the
main bearing and connecting rod.
-
Inspect the mating surfaces on the crankcase
halves for scratches or deformations, taking
particular care with the surfaces that mate with
the cylinder and the mating surfaces between
the crankcase halves.
-
Defects in the gasket between the crankcase
halves, or the mating surfaces shown in the
figure, can cause a reduction in the oil pressure
lubricating the main bearing and connecting rod.
-
Check the main bearing seats that limit axial
play in the crankshaft show no signs of wear.
The dimension between these seats is measured
Summary of Contents for GT 200
Page 1: ......
Page 90: ...90 9 1 2 Turn Signal Lights Horn Services and Accessory Pre Wiring ...
Page 151: ...151 10 10 Lubrication Circuit ...
