Hi All,
A couple of trips ago I noticed my 430 occasionally faltering for a split second while driving. It felt like the ignition was momentarily disconnected then reconnected. Just this weekend it got worse to the point where it was happening continuously to the point where the engine stalled and wouldn't restart.

When it was cold I managed to get it to run again and put it away to investigate. I can barely get it to idle and when it does it runs really roughly. Using the timing light I determined that all 8 cylinders are sparking very erratically, two hardly at all. I have checked all the ignition parts (resistor, coil, spark plugs, leads, distributor) and everything seems to be OK. The mixture and timing were correct before things started going wrong.

Would anyone be able to suggest what might be wrong ? Apart from electrical components I'm not sure what would deteriorate so fast (within the space of a few trips). Please let me know if you need further information.

Thanks so much
John

I had a similar problem that figured out to be just the carb's fuel bowl. It had gathered dirt from an inefficient fuel filter. The particles disturbed the needles' movement into the seats etc.
Just a thought.

If you are sure that you have erratic spark then the problem has to be in the distributor. If you have point type ignition, point gap is very critical. Worn bushings etc. can make accurate adjustment impossible. Check for worn bushings by pushing the shaft from side to side with the points on the highest part of the cam lobe, observing how much the gap changes . Also the pivot on the plate the points are fastened to can wear out,very common problem on older Ford distributors. You need to attempt to wiggle the point plate also. Good Luck !

If the fuel pump is working ...then check the little braided ground wire it may be on the verge of breaking...
I had that happen on my 59 Lincoln...
Use a match book cover to check the point gap....
Check the connections at the ballast resistor, check the resistor ....then the coil .....

I second the resister and coil check. I do not know if you have a resister before the coil on your car, but it is worth a couple minutes to check the voltage to it. It will be 9 or 12 volts and you need to run the right coil.
Had the same thing happen to me on an old Ford Van. No resister and the coil overheated and the ignition acted up and finally quit. The engine and coil cooled down and would start again. Was a 9 volt coil that was supposed to be used with an external resister. I replaced the coil with one that had a built in resister and no more problems. A voltmeter will tell you what coil to use. Good luck. TJR

Hi All,
Thanks so much for your advice. I'll work through all of these suggestions and see how things go.
To answer one question, yes it's separate coil resistor set-up.
Thanks so much
John

OK back again.
I finally found the problem. Only a few months back I did an igntion overhaul - replaced plugs, leads, distributor cap, rotor, points and capacitor. Apparently the new capacitor I bought was not of good quality and after only a few months of operation it developed a fault where once the engine heated up it would malfunction and cause the ignition to fail. Another capacitor fixed the fault. Apparently you can't even rely on new parts...
Thanks everyone for your advice.
Tim