Sudden failure to start!?

Hi there people, I have an '87 1.6 carb cabby that was running fine past few weeks, last night I had abit of a drive but nothing major only about 60 miles and it was fine, this morning at 8.30 we went down to the stables and it was fine and on the way home at 9.40 and was still good, then went to get in it at 10.20 and it wouldn't start! I've checked fuel n that's all good, then I checked spark plugs and they don't seem to be sparking, they were new a month and half ago so can't be them! What could have happened so suddenly to my car? Any help much appreciated!

Sounds like a broken wire or coil or dizzy hall sender failure.

Or maybe even as simple as a fuse.

I have seen ignition switch failures do this as well.

Hi thanks for the reply! Yea I though it could be the coil pack or that hall sender thing, what does that actually do lol? And are they easy to change? How do I test my coil and hall sender? I checked my fuses and they were all ok, and it turns over fine just no spark! Thanks for any more help

The hall sender varies its voltage output in the presence of a magnetic field. The dizzy has an aluminium cylinder that has 4 magnets placed at 90 degrees to each other, so as the dizzy rotates it will trigger a pulse from the Hall sender, this in turn gets amplified by the switching transistor (the one in the scuttle tray) which sends a pulse to the coil - the coil is a transformer which will transform a 12 volt pulse into several KV for sending to the the rotor arm and then on to the correct spark plug.

To test the hall sender you will need a voltmeter - do a google for "Hall Sender Testing", there are a few guides out there.

You can get a new hall sender for some dizzys, might just be quicker and easier to replace the whole thing though.

Yea man cool, thanks for that! The hall sender I the 7 pin thing in the scuttle isn't it!? Well, it started today!! I don't actually know how I fixed it either lol! I tried turning it over and it still didnt start, so I just took a few electrical plugs out to make sure there was no dodgy connections And I made sure they were all pushed back on properly, also just made sure all ht leads were on the plugs properly and then tried it and it started straight up! Strange! Now I'm paranoid to drive it though incase it decides to not start for me again randomly :s

Great to hear she started !!

The hall sender is inside the dizzy. The scuttle holds the TCI unit, basically it is a big transistor that amplifies the signal from the hall sender

Oh right, I see! It seems to be running rough at low revs now though, like a slight misfire sometimes, and it idles rough now too lol! Do u think my cool could be on the way out or something?

the fact it started after wiggling sounds to me like you have a dodgy wire/pin somewhere. go back over the tci loom end to end looking for black tape, be sure to peel back all the rubber boots and check inside for damage and loose wires etc.  check the ends of the pins to make sure they're all straight and tight, if the pin ends have opened up a bit try to bend them closed again.

try fitting new cap, arm, leads and plugs while your're in there be sure to buy decent quality bits:
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