Morris Minor Owners Club

Total and unexpected ignition fail this morning, loads of electrical power, nice strong starter motor action, loads of fuel that came out of the filter when I checked it, then the rotor arm with this burned edge, could that be the cause of my ignition failure? or do I need to check deeper?[frame][/frame]

Do you have electronic or points?

Could be a faulty condensor.

Normal - give it a wee rub with glass paper. Look elsewhere for the problem....

I once had a rotor arm fail, you could see the electrical tracking line across the bakelite as it went to earth

my first port of call would be condenser ,do u have a spark ?at the plugs, at the points do you get a light when testing?

thanks guys I'll check that. thanks for the replies.

I also recall there was much grumbling about some red rotor arms on the forum in the past. Perhaps yours is one of the poor quality batch?

My dizzy is electrical not points, would that effect the rotor arm and prevent ignition[frame][/frame]

Couldn't say myself, as I've always used points, but I understand if electronic ignition goes wrong then it's kaput.

Someone will be along who knows about electronic ignition.

David
I switched from your restoration post to this one.
Can you tell us which type of electronic ignition you have fitted please .There a great number on the market.
Bob

thanks Bob, I can't tell you what model it is, I don't have the packaging any longer, Ive ordered a new coil,rotor arm, spark plugs and leads, they should arrive tommorrow, I'll fit them and see if it starts, I have no idea how to test this electrical distributer to see if it is the item causing the fail.

This is the problem with leccy ignition. When it fails - hard to find the cause. It could be the rotor arm - maybe tracking we can't see in that picture. Oh, and it's NEVER the coil..........

I've removed the spark plug from the 2nd cylinder from the front just to see if it's causing a problem by being heavily coked up.[frame][/frame]

Well - it's NOT heavily coked up......

when I turned on the ignition switch and placed the positive probe from my multi meter on the metal connector of the coil and the earth probe onto the block, I got 4 volts showing on the meter.But an ohms test on the coil gave a 1, very low resistance.

David
Checking it out from your photo, I believe you have an Accuspark ignition system fitted.
Their website is http://www.accuspark.co.uk it has pictures, so you can confirm, or otherwise, it's what you have.
The website has a Help section, info on their returns policy, bits about Ebay purchases, etc.

I always fix my negative lead to the negative battery post when checking out battery voltage supply but it's a personal thing.
You need battery voltage ( circa 12.6 volts, healthy battery) on the low voltage side supplying power to the coil ( White wire ) and from the coil to distributor ( white/ black tracer ).Ignition needs to be ON but switch it OFF, immediately after you have done the test with your multi meter.

Warning remember Roy's law.. it's never the coil !
Coil tests.Ignition off, leads disconnected ( mark/ note / take photo ).Meter on Ohms setting , red lead to + terminal, black lead to - terminal.Ohms reading on the Primary circuit should be around , some books say 2 Ohms, others say 3- 3.5 Ohms for a Lucas 12v coil ( non ballasted ).
To check the Secondary circuit ( disconnected as before ) Meter on Ohms...red lead to the + terminal, black lead to the central terminal, where the HT lead ( coil to distributor cap ) emerges from. A reading of around 5 Ohms is typical.
Re-connect leads correctly.

My money is on the rotor arm,marking the wise one's words ( Roy's ) but time will tell.
If the other plugs are as black then you might want to weaken the mixture slightly on the carb.Turn the nut , clockwise, viewed from below.
Bob

Coil Primary definitely 3 to 3.5 ohms. The 2 ohm coil is for a ballasted ignition.

Roy
Thanks for clarifying the" ballasted coil " 2 Ohms " norm " reading, it's always puzzled me.Appreciated.
Bob

Hello Bob,

although I've never measured it, I'm surprised at the figure of 5 ohms as the secondary winding has a huge number of turns compared to the primary and of a very fine conductor, I would've expected much higher?

Alec

Alec
My source of info for that was Classic Car Electrical Systems Repair Manual Page 58
Bob