Electronic ignition on a Mk1.

[baconsdozen]

I took the motorhome out for a longish run yesterday. About half way down a busy five mile stretch of single carriage road with no pull ins the thing started spluttering and banging.I nursed it to the next turn off and within yards it spluttered to a halt. After a load of messing about I found the electronic ignition had gone up the spout.With the ignition on the coil was sparking at random with the points (the system still relies on them but needs no condensor) open or closed.I cleaned the points,then fitted a new set and even added a condensor but still the coil would fire randomly with the ignition turned on,the engine would fire but sound horrendous.
Finally I took the whole thing off and put it back to standard.
Electronics is a bit of a mystery but I cant see how a coil can spark with one end live and the other in effect disconnected. Anyone any ideas?.

[Ellwood]

the points activate the spark when they open, i had a set of points on a motorbike with a spark box and coupled up to electronic injection, and sometimes the injector gave a double squirt, even with new points. so possibly your system like gave a double spark???

Anyway on my MK 1 Tranny i fitted an Accuspark kit nr 19 and it is spot on. i have copper plug leads, and standard coil.

The only good to know bit is that you need to turn the distributor an 1/8th of a turn clockwise - the vacuum advance thingy ends up right against the rocker cover. this is because the little magnets in the pickup ring are not positioned on the lobes where the points would normally open, but between the lobes .

[DougT]

It might be the coil itself. With one side live, if the internal insulation of the 12v section of the coil has broken it could be earthing to the case which is nicely earthed to the chassis or to the earth side of the High Voltage part of the coil. With the standard set up there is not as much voltage on the 12v side so the insulation may be holding up.

If you have another coil to hand, I think it would be worth a try.

Cheers

Doug

[baconsdozen]

A mate put the old electronic system on a tester,he then spoke to me in some sort of foreign language,full of references to capacitors and 'trans' something or others (formers,istors or vestites) the only word I really understood was "knackered"