Morris Minor Owners Club

i seem to be having trouble with sparking at the plugs the points are sparking and the ht lead out of the coil is sparking when i open the points i have put a new cap on and a new capacitor when i put the lead back in the cap and turn it over no spark?

Hello Mixerman,
check the rotor arm closely for cracks, dirt or dampness.

Alec

Most likely the rotor arm or perhaps a dud distributor cap. Dampness / moisture in the leads can also be the culprit - my traveller refused to even consider firing once over Christmas until I gave the distributor/leads a quick blast with an electric heat gun. It started immediately after I did that.

the points are sparking

the points are not meant to spark (unless the condenser is faulty).
However that's a seperate issue, and it may well be your rotor arm causing the lost spark. There are a bunch of dodgy rotor arms around that leak throught to the distributor spindle.

COME ON RAY.....you should get a spark at the points if all is well
when you open the points with the ignition on...it is one of the easiest
ways to see if voltage is present up to that point, I know what you mean
but you will mislead many of the less knowledgeable members.

I know what you mean
but you will mislead many of the less knowledgeable members.

hmm - fair point ;-)

thank u all 4 your replies i will buy a new roter arm but of interest how do u know that that carbon thing in the middle of the distributer is touching?the rotor?
phil
1960 minor 4 door in good nick (susie)

Hello MM,

you don't unless you actually measure the distances. It is not a usual trouble area however.

Alec

It sticks out about 1 cm and you should be able to push it up by that amount (a spring pushes it back). As long as it does that it should work, but you never know.

This is why I keep old dizzi caps, rotor arms etc - you know they worked when they were replaced and they can be used to test new items.

Usually the centre of the rotor arm polishes up with a ring type mark.

Usually the centre of the rotor arm polishes up with a ring type mark

I was brought up with the fact that 99% of starting probs; is confined to small dirty connections in and around the distributer area. I always polish the rotor arm twice a year with auto-sol ( only takes a minute) gently scrape the connections that the rotor arm touches and then wipe over with a fine emery paper, and then scrupulessly ( think that's spelt right !!! ) clean both inside and outside the dizzy cap, not forgetting to take each lead out and clean the lead and the ends. Some people use wd40 or similar stuff to spray on, but I have never used it and just keep everything clean and dry..... Never had any probs; in over 40 yrs.
Hope this helps....
Mal

Usually the centre of the rotor arm polishes up with a ring type mark.

Mal my remark relates to how you can tell if the carbon contact in the centre of the cap is touching or not as requested by Phil and not how to keep things clean.

Kevin...

I was just trying to be helpful and offer years of experience.....not stand on your toe's..............
Mal

No problem Mal its just that your posting quoted mine and I did not want it to confuse Phil.

OK Kevin..

Sorry for any misundestanding.

Mal

Thank u 4 replying but i have the same problem i have bought a new cap and took the points out they was a bit black so i cleaned them up i have checked the rotor arm and polished it! i can see marked on the rotor arm and on the thinghy in the middle of the cap , so i know they are making contact i have gone back to test the coil took the HT lead out of the cap and IGN on turned it over by the starting handel and it sparks like hell , i am baffled
phil.

Phil,

If you've got sparks at the coil, have you got them at the plugs?

If the sparks are present at the plug ends of the HT leads, then the plugs are suspect (either the insulation outside the cylinder or inside).

Have you tried (yet another) set of new plugs? It is possible for the insulation to give up under the compression (so it looks ok outside the cylinder)

Luck,

colin

I'm ignorant as pig manure and should not comment on this case. On the other hand mirium gave up the ghost on Marlow high street last week and a similar thing had happened.

I couldn't get a spark for love or money. Eventually I "wibbled" the contact breaker springy end (where the nut is) and there was a small ammout of arching. The breakers couldn't find a ground because the nut ont he top had worked loose and stopped it. If you put the washers in the wrong order then the same thing can happen.

Probably not what has happened to you but worth a check.

Colin.
i have a spark up to the ht lead as it comes out of the coil i have even put it back and touched the carbon bit in the cap and it gave me abit of a shock as i turned the handel so i am thinking it can be only one thing the rotor arm but it looks perfect to me this may be a silly question but does the end of it wear so much that it is to far away in the cap to make a spark phil

Phil,

Just so I understand:

You have bit fat spark at the Coil

You have a bit fat spark at the HT Lead as it goes ito the distributor

No sparks at all out of the distributor.
(so no spark at ht lead, nor at plugs).

So, it's either earthing inside the distributor - usual causes are damp, cracked cap etc (but you've changed the cap.

or. the spark isn't getting to the four contacts inside the cap.

ok, the rotor drive is going around (cos the points open & close).

Hmm, silly question time:
Is the distributor cap the correct one for your distibutor?
same thing for the rotor arm?

What engine size / model do you have?
p.s. what type of HT leads (copper/ carbon/supressed)?

Colin