Powerdynamo, wrong timing after engine repair

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Inition timing wrong after  engine repair (new or repaired crank)
This information  may be used to check and set timing in all Powerdynamo 2 stroke alternator-based ignition systems on cranks turning clockwise.

We have again and again customers who have problems with timing of systems using a woodruff key to fix rotor position but have wrongly assembled crankshafts which have the woodruff in the wrong place.

Those problems, as others, may be easily solved as described below:
Systems with external triggering (Sensor S01)
For internally triggered systems see below

Pull the woodruff (or pin).
No worry, your rotor will still hold on to the shaft
Have a look at the new rotor. You will find on its circumference one or two elevations. Those are trigger signs. DO they near the sensor core (the metal pin in it) ignition is triggered (on 2 strokes without advance control only)

To set timing, you bring the piston into correct firing position (see your manual) and than set the rotor in such a way onto the shaft that the start of its elevation is just at the sensor pin (see sketch)
both markings align.

Check that the gap between sensor and rotor nose (elevation) is 0.3-0.4mm (if you have more engine has starting problems)

Note: on systems with advance control this is different! See here
Experience tells us that one problem never comes alone. Others might well be lurking somewhere.

So at this point please check that
  • rotor can move freely above the coils and does nowhere collide with anything (cables included)
  • check that sensor core and rotor nose are in lane and not shifted as shown in problem sketch. This can happen after shafts have been repaired or replaced by others. More information on this and a solution see here.
Systems with internal trigger


Have a look at the rotor (flywheel). 

On its circumference you will find a small lasered on line
(older versions pressed in line).

Have a look at the stator carrier plate (aluminium). There you will find (depending on diameter) at the perimeter or further inside a few small holes (or half holes). 

On such arrangements identify the hole (halfhole) situated most to the left as shown here in the picture.

NOTE that this is valid only if the stator wire goes through the plate opening next to the marking (here indicated as a round black plot). If the wire has to go through the other opening than the marking should be shifted 120 degreed clockwise.



As mentioned on larger plates of this type the marking is a complete hole (not only a half one) and is situated further away from the perimeter.


Note that the above shown markings are valid only for clockwise turning systems.


On plates of other construction, as on anticlockwise turning systems we set a small dot or line on the plate (normally indicated in the corresponding instructions)

For systems with advance control also see information here.
At the moment ignition is triggered, both the rotor line and the shown base marking align.
To set timing, you bring the piston into correct firing position (see your manual) and than set the rotor in such a way onto the shaft that both markings align.
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