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MG Midget and Sprite Technical - 1500 engine died

I've just returned home after having the engine "die" with no warning. There were no hiccups, coughs, or warnings. So at the moment she's parked in a small lane approx 5kms away.
I've got fuel at the carbs, but no spark.
Am I right to think coil, or condenser.
Thanks, in advance, for any help.
Graham

Rotor arm?

It is easy to check the coil. Remove the king lead from the centre of the distributor cap and see if it sparks to earth when cranking the engine. If it does, then you are losing the HT between there and the spark plugs. Most likely the rotor arm or dissy cap.

If there is no spark from the coil lead, you need to check that you have power to the coil. Easily done with a simple test lamp.
Dave O'Neill 2

I've had several coils fail in the past 40 years of driving, but mine have given warning...backfires, rough running, etc. I've had a multitude of condensers fail with no warning, especially in the past 10-15 years (most were Mexican made).

A quick test of the condenser is to remove the distributor & crank the engine you should see a spark across the points each time they open & close. A quick test of the whole distributor is to use a test light: aligator clip on battery negative, pointed probe on coil negative terminal & crank the engine...light should go on & off rapidly as the points open & close...if this test is good, I then look at the coil. Coils can fool you, you can ohm them out, but may read good when cold, then break down when hot...I usually just replace the coil with a known good one as a test...a fairly quick & SURE test.

I've had so many condenser failures over the years, on automotive, marine & industrial engines, that I don't mess with them anymore. I convert to electronic. In the States, Pertonix offers very reliable upgrades.

Dave
DL Rhine

Thanks for the emails.

Three points go to Dave O'Neill as it turned out to be the rotor arm. I've never had one go terminal instantly before, so now it's replaced, we're on again for the Circuits des Remparts this weekend.

Thanks again.
Graham

De rien
Dave O'Neill 2

Good news, Graham! I'd have suggested the condenser as Dave did, having had several stalls due to the condenser in the past, before actually diagnosing what it was and replacing it with a new one - and eventually with a pertronix.

And yeah, rotor arms can be devious. They can look like new while being quite faulty.

Best,

-:G:-
Gryf Ketcherside

This thread was discussed between 13/09/2009 and 17/09/2009

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