Morris Minor Owners Club

I have a POSITIVE earth setup in my Minor. Basically the standard setup from the factory with dynamo and Lucas 25D distributor.

I have ordered an Accuspark positive earth 25D distributor. I ordered this rather than just the module because my distributor is quite worn and elderly.

I have had a look at the installation instructions on the web. Part of the installation is to make a new wire and connect the + side of the coil to earth. It is suggested that the coil mounting bracket could be a suitable earthing point. I wonder how I might achieve this in a neat and tidy way?

I can solder but I don't know much about car wiring at all. I am thinking I will need Lucar type connectors on both ends of a piece of wire of appropriate diameter, (I think some is supplied with the kit but not the connectors) and then maybe solder a blade connector to somewhere that doesn't show on the coil mounting bracket. Does that sound right?

Thanks in advance for any advice.

The wiring diagrams and instruction from Accuspark are here: https://www.accuspark.co.uk/Instruction ... ctions.pdf

So far I have ascertained (by measuring) that the blade connectors on the coil are 6.4mm and that 1mm automotive wire is rated at 16 amps.

The obvious solution would be to earth via one of the bolts that secure the bracket.

myoldjalopy wrote: ↑Thu Dec 08, 2022 6:43 pm The obvious solution would be to earth via one of the bolts that secure the bracket.

Yes indeed but just stripping the insulation off the wire and trapping it under a bolt seems a bit shoddy? Maybe solder the wire to the bolt washer?

svenedin wrote: ↑Thu Dec 08, 2022 7:33 pm

myoldjalopy wrote: ↑Thu Dec 08, 2022 6:43 pm The obvious solution would be to earth via one of the bolts that secure the bracket.

Yes indeed but just stripping the insulation off the wire and trapping it under a bolt seems a bit shoddy? Maybe solder the wire to the bolt washer?

Use a Ring/Eyelet terminal.
Regards John

svenedin wrote: ↑Thu Dec 08, 2022 7:33 pm

myoldjalopy wrote: ↑Thu Dec 08, 2022 6:43 pm The obvious solution would be to earth via one of the bolts that secure the bracket.

Yes indeed but just stripping the insulation off the wire and trapping it under a bolt seems a bit shoddy? Maybe solder the wire to the bolt washer?

A less shoddy alternative would be to strip the wire, as necessary, and crimp on a proper connector?

StillGotMy1stCar wrote: ↑Thu Dec 08, 2022 8:15 pm

svenedin wrote: ↑Thu Dec 08, 2022 7:33 pm

myoldjalopy wrote: ↑Thu Dec 08, 2022 6:43 pm The obvious solution would be to earth via one of the bolts that secure the bracket.

Yes indeed but just stripping the insulation off the wire and trapping it under a bolt seems a bit shoddy? Maybe solder the wire to the bolt washer?

Use a Ring/Eyelet terminal.
Regards John

Thank you. I wasn't joking when I said I didn't know much about car electrics. I just didn't think of using a ring terminal. In all the time I've had that car, 33 years, I have never once altered the wiring or changed a connector! Well not on the car anyway. I did solder on a ring terminal for a wire in the fuel pump ages ago but for some reason the thought did not occur to me to use one here. An 8.4mm ring terminal will be ideal (I measured the stud thread) so I have ordered some and some appropriate wire and spade connectors.

When I do this job I am going to have to be careful to check the existing wires to the coil and not assume the coil is wired correctly. The existing wires are supposed to be white with black tracer to + coil and white to - coil but in fact both wires look as though they are white with black tracer (probably old oil). Since one wire goes from the coil to the distributor I can just check continuity with a multimeter at either end of the disconnected wire. I do know how to do the timing (or at least I did a long time ago). Something to keep me amused over the Christmas holidays.......

I have made up a wire that connects from the + side of the coil to earth on the coil bracket using a ring crimp connector. I bought myself a Draper ratchet crimping tool as I anticipate it will be useful for many other jobs. As this topic of a Positive Earth Accuspark does not seem to have been covered before I will post further as I move on with the job.

I too fitted a complete +ve earth Accuspark distributor some time ago. I ran a black wire, with a suitable eyelet, and connected it to a top dynamo bolt.
That distributor does require a bit of alteration to the original!
That's it below the temp. gauge sender. The wire is routed under the coil and hardly visible.

Svenedin, a good job but the plastic cap for the Lucar terminal is on the wrong way round.

How can it be the wrong way around when the wide end is over the terminal and narrow end over the wire?

See:

paul 300358 wrote: ↑Thu Dec 15, 2022 4:03 pm Svenedin, a good job but the plastic cap for the Lucar terminal is on the wrong way round.

Ok thanks I’ll have a look. I didn’t actually fit the Lucar connector. That red wire was supplied by Accuspark with the Lucar connector already fitted. I just added the eyelet.

Stephen

Agree that Lucar connector seemed suspect. The connector rattled in the plastic housing so I changed it to a different fully insulated crimp connector. I also changed the wire to something of better quality and of the known correct amperage. Crimp connectors are a novelty to me and rather fun! Although I have the time it's much too cold for me to be working in the garage today so the rest will have to wait.

I think the coil's support which clamps around the dynamo has insulation to isolate the coil from the dynamo.
I have just checked with a meter and there is no continuity between the coil's body/+ve terminal and earth with it mounted in place on top of the dynamo.
If, in your case, it's the same, that red wire will not earth the coil.

Thank you! I will test whether the earth is good or not with a meter and may have to redo this to Earth somewhere else.

It could be just that, on the one I checked, there isn't a good connection between the bracket and dynamo, eg. paint. I'm probably wrong re insulation. It's not often I'm right and I'm no doubt wrong again.
Worth checking for continuity once everything is fitted and wired up. Easy enough to re-route to a better earthing point or, even easier, scrape off some paint!

Not at all. It's really worth pointing out and checking. I can easily check for continuity. It will save a lot of confusion if I can't start the car due to a bad earth connection.

mobylette wrote: ↑Fri Dec 16, 2022 8:00 amSee:

Your picture is wrong way around or incorrect insulator.

Bill_qaz wrote: ↑Fri Dec 16, 2022 5:59 pm

mobylette wrote: ↑Fri Dec 16, 2022 8:00 amSee:

Your picture is wrong way around or incorrect insulator.
Screenshot_20221216-175620_Chrome.jpg

Thanks I’ve changed it now.