Morris Minor Owners Club

Hi,
Mitsy was misfiring a little when we picked her up so I did a service and changed capacitor, points, distributor cap, leads and plugs. Set the gaps and gave her a go. Now she won’t start. She cranks happily but have done the usual checks and there is no spark at the plugs or distributor. The coil got quite hot and when I took the lead off to check I hadn’t fitted it wrongly some oil? came out of the end. Is the coil fried?
Thanks in advance.

I would suggest that the coil is 'fried' and a replacement is necessary.

I would concur with Phil, if you have a multimeter you can do a resistance check on the primary and secondary windings but replacement is not expensive and if not that you have a spare. Have you checked for spark at your newly fitted points, ign on and flick them open and closed with screwdriver. New points sometimes are coated and need a clean.
You did put the rotor back? You wouldn't be the first to have left it out

Please don't be offended, but have you used the plastic insulators and fitted the condensor and l.t. connectors under the top insulator and connected to the top of the spring?
Yes, I did that wrong once.
The coil's primary and secondary windings resistance can be tested if you have a multimeter.

Thanks Bill. I wouldn’t put it past me, I was pretty tired by the end . The rotor arm was on and even tried the old one just in case.

Olonas, I think you might be onto something.
I put the black and orange wires under the nut, not under the insulator onto the spring!!!
I will let you know what happens .
Many thanks.

Phil, I’m ordering a new coil. It seems like a sensible thing. Thanks for the reply

I have 1 ohm across the coil windings. Is that ok?

LorliC wrote: ↑Thu Jun 20, 2024 9:06 am I have 1 ohm across the coil windings. Is that ok?

The coil primary should be 3-4 Ohms - so 4-3 Amps when connected to a 12V supply

Little wonder the coil was leaking oil, if it was potentially drawing nearly 150W!

A simple way to test a coil is to hold the king lead about 6mm from an earthed surface and flick the coil supply on and off. A lack of big fat blue sparks is a good indication that a coil is past its use-by date.

LorliC wrote: ↑Thu Jun 20, 2024 9:06 am I have 1 ohm across the coil windings. Is that ok?

Here is an example, your 1 ohms is OK allowing for a bit of meter tolerance , you need to test secondary.
https://www.gomog.com/allmorgan/coiltes ... 0defective.

Note different reading for ballast and non ballast coils in the article

Bill_qaz wrote: ↑Thu Jun 20, 2024 10:08 am

LorliC wrote: ↑Thu Jun 20, 2024 9:06 am I have 1 ohm across the coil windings. Is that ok?

Here is an example, your 1 ohms is OK allowing for a bit of meter tolerance , you need to test secondary.
https://www.gomog.com/allmorgan/coiltes ... 0defective.

1 Ohm resistance is not OK if this is a standard coil. It should be 3 Ohms or very close to that. In any case, if the coil is leaking oil it is going to fail very soon if it hasn't already. I suspect it failed internally, overheated and that has caused it to leak. A new 3 Ohm coil is needed.

Choosing a new coil is not especially straightforward because unfortunately there are a lot of poorly made coils out there. The standard design is oil filled. A more modern design is a resin filled coil. The resin filled coils are less susceptible to failure from vibration and this is a particular concern with Minors where the coil is mounted on the dynamo.

The best currently available coils are made by Pertronix so I am told by Martin Jay who is "Distributor Doctor". These coils are expensive but extremely reliable. Note that the Pertronix coils are larger in diameter than standard coils and need a new matching bracket.

I have used Pertronix coils for years without a failure yet. Many Minors are still using ancient coils which does show they were made a lot better back then.

Stephen

Thanks Steven,
I will probably grab a spare coil but the Lucas sports coil is in and she’s purring like a kitten!
Thanks for all of the help.

LorliC wrote: ↑Thu Jun 20, 2024 12:25 pm Thanks Steven,
I will probably grab a spare coil but the Lucas sports coil is in and she’s purring like a kitten!
Thanks for all of the help.

Great news! Happy motoring.

Stephen

LorliC wrote: ↑Thu Jun 20, 2024 12:25 pm Thanks Steven,
I will probably grab a spare coil but the Lucas sports coil is in and she’s purring like a kitten!
Thanks for all of the help.

So was a failed coil the issue?

It's never the coil.
RIP ROY
Regards Win

I wired it wrong, I put the orange and black on top of the insulator on the points. I think the coil was shot anyway, there was oil oozing out of the top. She tried starting with the old coil but now runs sweetly with the new one.

I really must remember to do these jobs with my readers on