First trip out...

[David]

Re: First trip out...

Thats an earlier type ignition switch with only 3 positions so no problem there, had to dig out an old Morris Minor manual to check the wiring.

That's good to know, thanks Ben.

[David]

Re: First trip out...

Well the very rough idle has been mostly cured by putting some oil in the Stromberg dashpots!

Still not starting easily, but more success with the bonnet off and I can see the cables are fouling on it so there's a clue. Will get the new coil and Powerspark on this weekend along with a clean and gap on the plugs.

It's running very rich, but then the air filters are black, will whip those off at the weekend and also give the carbs a good clean and adjust.

I'm beginning to realise that the last owner is probably a very good cabinet maker

[David]

Re: First trip out...

So, I fitted the Powerspark module today and guess what no spark now. I'll sort it tomorrow but meanwhile I noticed that the coil appeared to have the wire from the ignition plugged onto the negative terminal of the coil. The wire diagram(s) confirm that it should be on the positive terminal but just posting here to double check with you guys

[b_caswell]

Re: First trip out...

Perhaps someone used the Morris Minor wiring diagram for a positive earth car if your car is negative earth then the live feed should go to the + or sw connection. Cant comment on the power spark but it wont like being wired up backwards. I hope it hasnt gone pop!

[David]

Re: First trip out...

Perhaps someone used the Morris Minor wiring diagram for a positive earth car if your car is negative earth then the live feed should go to the + or sw connection. Cant comment on the power spark but it wont like being wired up backwards. I hope it hasnt gone pop!

No, the Powerspark is wired up correctly, just the ignition to coil feed on the wrong coil terminal.

[stevejgreen]

Re: First trip out...

There is an interesting article here or there that explains the working of the ignition coil, and though it is specifically MGA the same principles apply.

Solid state/electronic ignitions work primarily by producing a cleaner more powerful switching than the old points systems, this generates a much more abrupt change in voltage in the primary and secondary coils. There is always the outside possibility that you already had a ageing ignition coil, and this more abrupt switching, has found a weak spot in the coil windings that may not be detectable with an ordinary ohm meter, as the coil can generate well in excess of 1000V, enough to jump tiny breaks in the insulation.

Many modern electronic devices, though I can't be specific about a Powerspark, are designed with polarity or incorrect wiring safety features. Often these are added in order to minimise the cost of running a customer help desk and returns departments than for the more obvious reason, the cost of the extra circuitry being minimal during manufacture.

[David]

Re: First trip out...

There is an interesting article here or there that explains the working of the ignition coil, and though it is specifically MGA the same principles apply.

Solid state/electronic ignitions work primarily by producing a cleaner more powerful switching than the old points systems, this generates a much more abrupt change in voltage in the primary and secondary coils. There is always the outside possibility that you already had a ageing ignition coil, and this more abrupt switching, has found a weak spot in the coil windings that may not be detectable with an ordinary ohm meter, as the coil can generate well in excess of 1000V, enough to jump tiny breaks in the insulation.

Many modern electronic devices, though I can't be specific about a Powerspark, are designed with polarity or incorrect wiring safety features. Often these are added in order to minimise the cost of running a customer help desk and returns departments than for the more obvious reason, the cost of the extra circuitry being minimal during manufacture.

I went for a new coil at the same time.

[philcoyle]

Re: First trip out...

You may wish to keep in mind that coils for electronic ignition are completely different to a standard points type ignition.
Points type coils will work on an electronic system, but poorly.

[David]

Re: First trip out...

You may wish to keep in mind that coils for electronic ignition are completely different to a standard points type ignition.
Points type coils will work on an electronic system, but poorly.

Thanks Phil. I ordered the coil with the ignition module so presumably I got the correct type, but must admit I didn't specify a matching unit!

[David]

Re: First trip out...

So, I'll close this thread as the starting issues are all sorted. Need a tune to timing and carbs as well as some replacement parts.