Engine Construction - O.S. engine FL-70 Owner's Instruction Manual

ENGINE CONSTRUCTION

With this engine, the piston will
feel tight at the top of its stroke
(TDC) when the engine is cold.
This is normal.
The cylinder bore Is a little
tapered.
The piston and cylinder are
designed to achieve a perfect
running clearance when they
reach their running temperatures.
Cylinder Liner
Crankshaft
A little tapered
When the engine is cold. When the engine is hot
Piston