Earthing the ignition coil - or not

[RichardS]

I am in the process of replacing a Lucas Sport coil with ballast resistor for a Bosch Blue Line coil - I no longer need the ballasted system.

Looking back through the archives there have been previous debates on earthing the coil case.

The Lucas coil body was eartheda nd on checking with a multimeter the metal body is in circuit with the terminals.

However on the Bosch coil [which has a metal body too] there is no connectivity between the terminals and the body so I cannot see the need to earth the body. As described in an old previous post from Rohan elan-f15/coil-and-distributor-wiring-t1502.html I figure the HT circuit earths through the LT circuit and does not involve the metal body.

Is my reasoning sound?

Richard

[neilsjuke]

Best to earth it if the coil was to have a insulation fault the body would then be live and a spark to your hand or some petrol related earth point would not be welcome. You will need to earth if fitting a 1mF cap for radio suppression .
Neil

[RichardS]

Thanks Neil - sounds sensible.

Richard