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My TS250/1 missfires when the engine gets hot, but only under 3000 rpm`s. And under 2000 rpm`s does the engine stop but is easy to start directly again. There is 6,5 volts on the battery and new parts on the ignitionsystem...but.......can it be the condensor, points or the coil?

hi there,

do you have measured the Voltage directly on the ignition coil? Point 15 and 1? if you turn the crankshaft, the voltage must toggle 6.5V and zero. If the Voltage is lower than 6V it might be the Problem, maybe the connection anywhere between battery and coil or Battery and engine-ground. PS: do you have measured the voltage at the runtime of the engine or at stop? and...above what RPM is charging the battery?

Robert


EDITH:// you can have a problem with the sealings of the crankshaft, they have less power if they are gettig warm/hot...

It charges 7,4 volts on the battery.

you have tried another sparkplug? and... if you turn the machine on again, you have to open the gascock? and...how is the RPM of the motor in idle?

Robert

This obviosly a ignition problem, the idle is ok when engine not is to hot and it starts whitout the need to open the throttle.

ok, then it might be a problem with the capacitor. Because the capacitor dies sometimes if it is getting to hot. You have changed them?

Robert

I will change to a new one and see if it works better...

Good morning!

The mind behind that is, as lower the RPM, as higher is the current in the ignition coil and higher is the arc on the breaker that has to be cleared.

Robert