I have now finished the rolling chassis of my 1964 TES so time to start on the motor/gearbox unit. This is a 32A with Greeves cylinder and head. It was purchased as a loosely assembled non runner so before I strip the engine too far I want to check what it wrong with it.
Electrics
As found the engine had no spark when turned over but after some fiddling and cleaning the points it has a fat spark, but it is yellow not blue.
A meter on the wire from the ignition coil to the points gives 2.5 volts when the motor is turned over.
The resistance from the wire when disconnected from the points is only 1.1 ohms.
Is there a spec for these values as both these seem low?
I assume a blue spark should be possible?
Piston
As found the engine has no compression but lifting the barrel off reveals no rings. The piston to bore clearance is given in the Villiers service book as 0.008 thou max. Mine measures 0.007 so in theory just in tolerance.
What experience do others have with piston clearance as I would have thought 0.007 thou needs a rebore.
Should the Greeves cylinder use a head gasket.
Lastly the combustion chamber shape is only half the piston area. Should this chamber be at the front over the exhaust, or at the rear above the carb?
I have hopefully attached a picture of the engine. This shows terminals on top which I assume are redundant if I am using the bike for trials only. Does anyone know what the peg is that is threaded into the cases just in front of the terminals?
Thanks,
Peter
Electrics
As found the engine had no spark when turned over but after some fiddling and cleaning the points it has a fat spark, but it is yellow not blue.
A meter on the wire from the ignition coil to the points gives 2.5 volts when the motor is turned over.
The resistance from the wire when disconnected from the points is only 1.1 ohms.
Is there a spec for these values as both these seem low?
I assume a blue spark should be possible?
Piston
As found the engine has no compression but lifting the barrel off reveals no rings. The piston to bore clearance is given in the Villiers service book as 0.008 thou max. Mine measures 0.007 so in theory just in tolerance.
What experience do others have with piston clearance as I would have thought 0.007 thou needs a rebore.
Should the Greeves cylinder use a head gasket.
Lastly the combustion chamber shape is only half the piston area. Should this chamber be at the front over the exhaust, or at the rear above the carb?
I have hopefully attached a picture of the engine. This shows terminals on top which I assume are redundant if I am using the bike for trials only. Does anyone know what the peg is that is threaded into the cases just in front of the terminals?
Thanks,
Peter
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