No Spark

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hellen
Newbie
Posts: 2
Joined: Tue Aug 18, 2009 9:31 pm
MMOC Member: No

No Spark

Post by hellen »

I was recentley driving my morris and for no apparent reason it just stoped! I found that there was no spark. everything back to the coil was good,power was going in coil just nothing comeing out. New coil same problem, replacemet for new coil same problem can anyone help!!
linearaudio

Post by linearaudio »

Was it running badly before that?? If so I would suspect the points have closed up. If it was a sudden failure, maybe the contact in the middle of the inside of the distributor cap has broke/ gone on holiday. Take the cap off, look at that, check points are opening, and clean, and check the little earth wire braid which can break or come loose. If no luck, try replacing the condensor.
bmcecosse
Minor Maniac
Posts: 46561
Joined: Wed Feb 16, 2005 11:24 pm
Location: ML9
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Post by bmcecosse »

Welcome to the forum! So let's assume the coil is producing High Tension ok - from there it goes through a lead to the centre connection of the distributer (dizzy) - down a little spring loaded carbon brush onto the rotor arm. This rotates (surprisingly!) and distributes the High tension to each of 4 little terminals - which carry the current through the cap - and into the 4 HT leads which take it to the spark plugs. You found 'no spark' - so it must be getting lost on the way. Check the dizzy cap interanlly for any cracks or little 'tracks' where the current could be running to ground - check the carbon brush is present (and springy) - and look hard at the rotor arm for any flaws/cracks/loose rivet etc. I would say 'fit a new rotor arm' - but just try rubbing some clean engine oil over the surface ofvthe one you have - and then try again. This can 'rejuvenate' the arm enough to get it running (by sealing any cracks or tracks) - and it should be renewed as soon as possible.
Can I ask how you know there is 'no spark' ??
Are you sure the car hasn't stopped because of fuel pump failure - which accounts for well over 50% of ALL Minor breakdowns !
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hellen
Newbie
Posts: 2
Joined: Tue Aug 18, 2009 9:31 pm
MMOC Member: No

Post by hellen »

Thanks for the help,but as sod's law dictates the day after i put this post up and the 3rd coil it seamed to magicly cure it self,2 dodgey coils?
Arn't minors wounderfull cars!!!
Thanks once more and i will probaley be back with more questions.
LOL Hellen
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