Generic Race 50, Service Manual

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XII. Cylinder cover
Preparation data------------------------------------12.1
Fault diagnosis-------------------------------------12.2
Cylinder head --------------------------------------12.3
Examination of the cylinder head----------------12.4
Installation of the cylinder head --------------12.5
12.1 Preparation data
Matters needing attention in operation
In order to guarrante the sealing between cylinder head and cylinder block, the cylinder head undertakes a very big
bolt pretightening force.
Pretightening force value: 50Nm.
All parts should clean and blow cleanlily by high compressed air before inspecting and measuring.
The function of cylinder head: The cylinder head which seals cylinder block, consists of combustion chamber
with piston, bears high temperature, high pressure gas and finishs intake and exhaust through valve mechanism.
12.2 Fault diagnosis
Gas leakage between cylinder head and cylinder block or extra high combustion pressure
Cylinder head gasket breakage.
Cylinder head bottom plane warp
Combustion extra carbon deposit
12.3 Cylinder head
12.3.1 Dismantle
Loosen shroud fixing bolt.
Dismount shroud.
Loosen fixing nut and spark plug, dismount cylinder head.
Shroud
Bolt
Lock nut
Cylinder
head
Spark plug