Hrald 13/60 Misfires When Hot

[cbjroms]

Thanks guys, I am in Southampton. Anyone local who could lend me a generator and control box for fault finding purposes?

[cbjroms]

Decided to ditch Dynamo and Control Box and replace with an alternator.

Whilst awaiting delivery just prepping the wiring. As I understand it the alterantor has 3 terminals (2 x power and 1 x ignition light).Looking online the advice seems to be to put 1 x power to the +ve of solenoid and 1 x power as the feed to lights/horn/ignition.

Any reason I shouldnt put the 2 x power direct to solenoid +ve and the take one wire from solenoid +ve as power feed to lights/horn/ignition? This would just seem a neater solution.

[RobPearce]

There are two things to beware of when planning your alternator wiring.

First, there used to be some "battery sensed" alternators, on which one of the "power" terminals was actually a "sense" terminal. These MUST have both terminals connected together, but ideally at the far end (i.e. the battery, or as near as you can, meaning the solenoid). Fortunately, these are exceedingly rare these days.

Second, if you use two relatively thin wires to connect point A to point B, that does not necessarily give you as good a result as one thick wire. Any difference in length or condition results in imbalance of current. For that reason, if you're using both power terminals of an alternator, it's technically better to run separate circuits off them. Fortunately, the effect here is pretty minimal.

On two of my Triumphs, there is a relay (or two) in the headlight circuit, which is physically located forward of the alternator. Running a separate wire from the alternator to the relay(s) in this case is actually neater as well as more efficient than taking it via the solenoid.