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AJH[_3_] AJH[_3_] is offline
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Default Spark plug coil amplifier

On 11/04/2020 12:19, Dave Plowman (News) wrote:
In article ,
AJH wrote:
I stuck a coil out of an MGB into it, it gave a v weak spark but the
thing didn't fire even when spun up with a drill.. Just for interest
I'll mark the fan at TDC and put a strobe on it. It's a strange beast
in that it isn't piston ported and the carb is directly mounted on the
crankcase, reed valve I expect.


Dwell is important. This is the time volts are applied to the coil to
allow the flux to build up to the maximum, before they are interrupted and
the spark occurs.



Yes I didn't expect the car coil to do anything so there was a bit of a
bonus it sparked at all.

In the meanwhile I'm sitting back and taking stock. The owner says he
barely used the genset at all so I'm thinking it's more likely a problem
from having been laid up. Else it's one of those early problems that
show up from a manufacturing fault, typically the failure rate over time
is bimodal, a large number of faults in machines early in life then a
fault free period then an increase as items fail at end of life.

I've plenty else to get on with.