The Ford Barn

drolston · 10-10-2020, 06:41 PM

Good call Bill OH. The spark plug wire for #2 cylinder with the black plug registered open circuit on my ohm meter. The others read about 4,000 Ohms per foot, which is correct for spiral wound ignition wires.

Hoped it would be a bad crimp job, which would be repairable, but no, - the circuit is open somewhere within the cable.

Bill OH · 10-10-2020, 09:57 PM

Pleased that you found the open cable. You can either obtain a new spiral cable and periodically check the spirals for continuity or install Packard 440 wires, which in my experience are very reliable. You can put you hand around them and not get shocked. I will be interested in your reply of the performance that you have now achieved from your efforts.

JSeery · 10-11-2020, 12:00 AM

I think it is a no on the Packard 440 with the electronic ignition.

Bill OH · 10-11-2020, 09:34 AM

I think he is going to go to points and condenser - that is the reason for suggesting Packard 440. If he is going to stay with the Petronix then stay with the spiral.

drolston · 10-12-2020, 02:24 PM

Turns out the distributor end of #2 plug wire was broken. Replaced the end and measured continuity okay with the Ohm meter. But that cylinder was still not firing at idle. Replaced the carboned up and wet plug with a good plug (of a different type) and that cylinder now fires fine at idle.

I need to get the original (correct) plug back in before i give it the full throttle road test. I will clean up the fouled plug (torch, wire brush, carb cleaner) and report back.

tubman · 10-12-2020, 04:25 PM

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Why not get a new plug? I have seen situations where a plug will look perfect and still not fire. Had that situation just a week or so ago with the neighbor's lawn mower. He had put a new plug in it earlier this summer. All of a sudden, it quit and could not be restarted. He couldn't figure it out and ended up taking it to the local small engine place. The guy there had no pre-conception, put in a new plug and it fired right up.

drolston · 10-12-2020, 08:21 PM

Cleaning the plug worked! Now firing on all 8. Smoother, faster idle and passed the throttle slam test in second gear. Almost. No missing, but started to lose power approaching 4,000 rpm. Then remembered to turn the electric fuel pump on. That almost fixed the loss of power at high rpm. I think I will turn the fuel pressure up from 2.5 psi to 3.0 psi and call it a day.

Thanks to all for helping me through this trouble shooting adventure. Especially Bill OH.

Bill OH · 10-13-2020, 09:45 AM

Pleased that you found the problem with the ignition cable. You might keep in mind the size of power valves. As I mentioned earlier I had to go from #65 pv to 71 pv - half the size to prevent over rich mixture and bogging. I am running a 221 with Max 1 cam and dual 97s. And I can twist mine to 5500 rpm (1st and 2nd gear). Nice working with you. Enjoy your endeavor.

10-10-2020, 06:41 PM	#21
drolston Senior Member Join Date: Jun 2014 Location: Williamsburg, VA Posts: 1,627	Re: Missing at full throttle. Good call Bill OH. The spark plug wire for #2 cylinder with the black plug registered open circuit on my ohm meter. The others read about 4,000 Ohms per foot, which is correct for spiral wound ignition wires. Hoped it would be a bad crimp job, which would be repairable, but no, - the circuit is open somewhere within the cable.

10-10-2020, 09:57 PM	#22
Bill OH Senior Member Join Date: May 2010 Posts: 425	Re: Missing at full throttle. Pleased that you found the open cable. You can either obtain a new spiral cable and periodically check the spirals for continuity or install Packard 440 wires, which in my experience are very reliable. You can put you hand around them and not get shocked. I will be interested in your reply of the performance that you have now achieved from your efforts.

10-11-2020, 12:00 AM	#23
JSeery Member Emeritus Join Date: Nov 2012 Location: Wichita KS Posts: 16,132	Re: Missing at full throttle. I think it is a no on the Packard 440 with the electronic ignition.

10-11-2020, 09:34 AM	#24
Bill OH Senior Member Join Date: May 2010 Posts: 425	Re: Missing at full throttle. I think he is going to go to points and condenser - that is the reason for suggesting Packard 440. If he is going to stay with the Petronix then stay with the spiral.

10-12-2020, 02:24 PM	#25
drolston Senior Member Join Date: Jun 2014 Location: Williamsburg, VA Posts: 1,627	Re: Missing at full throttle. Turns out the distributor end of #2 plug wire was broken. Replaced the end and measured continuity okay with the Ohm meter. But that cylinder was still not firing at idle. Replaced the carboned up and wet plug with a good plug (of a different type) and that cylinder now fires fine at idle. I need to get the original (correct) plug back in before i give it the full throttle road test. I will clean up the fouled plug (torch, wire brush, carb cleaner) and report back.

10-12-2020, 04:25 PM	#26
tubman Senior Member Join Date: Dec 2013 Location: Minnesota, Florida Keys Posts: 10,303	Re: Missing at full throttle. Sponsored Links (Register now to hide all advertisements) Why not get a new plug? I have seen situations where a plug will look perfect and still not fire. Had that situation just a week or so ago with the neighbor's lawn mower. He had put a new plug in it earlier this summer. All of a sudden, it quit and could not be restarted. He couldn't figure it out and ended up taking it to the local small engine place. The guy there had no pre-conception, put in a new plug and it fired right up.

10-12-2020, 08:21 PM	#27
drolston Senior Member Join Date: Jun 2014 Location: Williamsburg, VA Posts: 1,627	Re: Missing at full throttle. Cleaning the plug worked! Now firing on all 8. Smoother, faster idle and passed the throttle slam test in second gear. Almost. No missing, but started to lose power approaching 4,000 rpm. Then remembered to turn the electric fuel pump on. That almost fixed the loss of power at high rpm. I think I will turn the fuel pressure up from 2.5 psi to 3.0 psi and call it a day. Thanks to all for helping me through this trouble shooting adventure. Especially Bill OH.

10-13-2020, 09:45 AM	#28
Bill OH Senior Member Join Date: May 2010 Posts: 425	Re: Missing at full throttle. Pleased that you found the problem with the ignition cable. You might keep in mind the size of power valves. As I mentioned earlier I had to go from #65 pv to 71 pv - half the size to prevent over rich mixture and bogging. I am running a 221 with Max 1 cam and dual 97s. And I can twist mine to 5500 rpm (1st and 2nd gear). Nice working with you. Enjoy your endeavor.