Dead 900SS

I was quite surprised that the rather expensive and quite new top of the range lead acid battery Died this winter as i lavished total care on it. But as it died during the really cold snap we had I put it down to experience.

Finally got round to fitting a new battery today (yup its been sat for that long- I’ve been buisy doing overtime to pay for the TT) and as I fitted it I got a splash off the connection. Well that explained the oroginal dead battery, the ignition switch had a problem and was draining the battery.

Then when I went to start it I found I had no spark on either pot.

Hmmmm, Ignition switch on all the time X left untill the battery is dead = Damaged burned out ignition equipment and coils.

  • lucky it didn’t catch fire I guess, especialy as I had my Oxy Propane gas axe set parked next to it!

Does anyone have the correct proceedures for testing all the bits (Original Boshe 79 sepc stuff) so I can work out what I need to replace,



Judging by the lack of replies, no one knows the correct resistance of the coils or how to test the Boshe box’s ect?

I left my ignition on for a few hours about 15 years ago, the coils got hot and …wax? dripped out of them, but they worked OK and they still do?
I’ve got a manual that covers the ignition resistances etc, I can send it to you, send me a pivate massage with your e-mail.

Hi Keef,

The standard ND coils are rated at 4 Ohms (with the ballast resistors adding another). There’s a test procedure for the coils in the Dramah workshop manual available here (look under ‘Manuals Index’)

I’ve never seen a test procedures for the Bosch boxes - I think people normally test them by replacement. Unfortunately, my spares are in store or I’d let you borrow one; but I’m sure someone else can help? For example, Andrew J. must have loads he’d be willing to send/sell you …

P.s The fact that both pots have lost their spark might incline me to look at shared components first …?

Just a thought …