Dead Coil?
Post Fiend
Joined: Apr 2002
Posts: 19,311
Likes: 97
From: Waterloo, Iowa
Dead Coil?
Dang. Ole Blue died while waiting to unload stuff at the landfill. Course I didn't bring my tools, guess I got complacent. Swapped out an old coil and it fired right up.
1. How do I test a coil to see if there are open windings or whatever?
2. Coil probably had 10,000 miles on it, but does say "Resistance Wire or Resistor Required" or somesuch. Assuming it's bad, did I burn it up? Does a 64 have a resistance wire on the ignition? How can I tell, and/or what value resistor/wattage do I use, etc. etc.
1. How do I test a coil to see if there are open windings or whatever?
2. Coil probably had 10,000 miles on it, but does say "Resistance Wire or Resistor Required" or somesuch. Assuming it's bad, did I burn it up? Does a 64 have a resistance wire on the ignition? How can I tell, and/or what value resistor/wattage do I use, etc. etc.
Laughing Gas
Joined: Oct 2001
Posts: 957
Likes: 3
From: Winchendon MA
Dead Coil?
To test a coil you just do a continuty test between the (+) and (-) terminals. It should be a dead short. Beawere that coils can and offen do "open" when hot that is to say after use they loose conductivity. As for the resitor wire I don't think you've got one. With the truck running check the voltage from the (+) coil terminal to ground it should be 8 to 10 volts if not add a ballasr resitor from any car or truck to knock it down some.
Just on a side note.
Make sure your coil is mounted upright with the high tention lead pointing up! So guys mount them laying down this leads to over heated coils due to the cooling oil not covering 100% of the windings. I made that mistake once and chased and ign problem for 6 mounths on a race car.
44Dwarf
Just on a side note.
Make sure your coil is mounted upright with the high tention lead pointing up! So guys mount them laying down this leads to over heated coils due to the cooling oil not covering 100% of the windings. I made that mistake once and chased and ign problem for 6 mounths on a race car.
44Dwarf
Post Fiend
Joined: Apr 2002
Posts: 19,311
Likes: 97
From: Waterloo, Iowa
Dead Coil?
Mount the coil upright? Hm. The bracket and such is set up for the coil to be laid on its' side. Never heard that before. I suppose I should just go to a pertronix electronic ignition but I'm a stubborn b#$stard as it is.
I read about 8 volts with the key turned to ON position at the points if I remember right. Wonder why the coil died so quickly. I'd think they last a hell of a lot longer than 10k miles.
I read about 8 volts with the key turned to ON position at the points if I remember right. Wonder why the coil died so quickly. I'd think they last a hell of a lot longer than 10k miles.
Post Fiend
Joined: Apr 2002
Posts: 19,311
Likes: 97
From: Waterloo, Iowa
Dead Coil?
Well -- they are installed on their side that way from the factory. But I checked the resistance of the "bad" coil -
From + to - side, I read 189 ohms, from + to coil tower 8,900 ohms, which is about right, I read somewhere primary/secondary should be 100/10,000... If it was toasted I'd think the secondary would be open or shorted. Then again, it might test OK at room temp. too. I suppose I oughtta just install electronic ignition too. Is there a drop in replacement for the 64's like Pertronix?
Supposedly no resistance wire or ballast will burn out points, but shouldn't bother the coil. I'll try swapping in the 'bad' coil again and see what happens. I'm leaning towards corroded wiring or something funky like that at this point.
From + to - side, I read 189 ohms, from + to coil tower 8,900 ohms, which is about right, I read somewhere primary/secondary should be 100/10,000... If it was toasted I'd think the secondary would be open or shorted. Then again, it might test OK at room temp. too. I suppose I oughtta just install electronic ignition too. Is there a drop in replacement for the 64's like Pertronix?
Supposedly no resistance wire or ballast will burn out points, but shouldn't bother the coil. I'll try swapping in the 'bad' coil again and see what happens. I'm leaning towards corroded wiring or something funky like that at this point.
Logistics Pro
Joined: Feb 2000
Posts: 3,565
Likes: 9
From: Sun River St. George
Dead Coil?
Ted, Do the Pertronix and add their coil as well. Install the later mode Ford flat cap, cap adapter and some fat 8mm wires. Then get some platinium plugs, gapped at 80 and forget about ignition troubles for good. Your truck will run better, start better and get better fuel mileage. I have used this setup for over 20K miles without any problems.
William in Atlanta
William in Atlanta
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Post Fiend
Joined: Apr 2002
Posts: 19,311
Likes: 97
From: Waterloo, Iowa
Dead Coil?
The Pertronix is a good idea, yes. But money is tight right now, for one thing, another is I like to keep things stock, and the troubleshooting aspect bothers me - I'd like to figure out what exactly the problem is/was.
Incidentally, what is the recommended tune up interval -- how many miles do plugs last with conventional breaker point ignition -- I've heard they don't last near as long than with electronic ignition. Points and condensor? Say, every 20K? 30K?
Incidentally, what is the recommended tune up interval -- how many miles do plugs last with conventional breaker point ignition -- I've heard they don't last near as long than with electronic ignition. Points and condensor? Say, every 20K? 30K?
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Postmaster
Joined: Apr 2002
Posts: 3,613
Likes: 6
From: Coal country
Dead Coil?
Tedster: IF your carb is tuned just right and IF your system is working well, you MIGHT get 10K out of a set of regular plugs. Sure they will keep working beyond that, but they just don't last as long. At least, that's my experience!
Logistics Pro
Joined: Feb 2000
Posts: 3,565
Likes: 9
From: Sun River St. George
Dead Coil?
Resistance wire is under the dash running from the ignition to the firewall (Pink) it will be warm when you touch it. Points rarely last 10K miles and will require readjusting (dwell) before that. And as they wear the timing changes and you get less fuel mileage and harder starts. I know the Pertronix is expensive 60 bucks or so, but IMHO beats the stuffing out of points. With Pertronix the timing doesn’t change, and once you have set the air gap neither does the dwell, ever. I expect to run my truck 30K miles before I clean and re-gap the plugs (22K so far). I will reinstall the plugs and run them another 30K. The flat cap gets 60K, rotor 30K, plug wires 60K. So in the long run all this stuff is cheaper. Besides after 22K miles my truck has never failed to start, runs really good and gets 12+ miles per gallon.
William in Atlanta
William in Atlanta
Freshman User
Joined: May 2002
Posts: 35
Likes: 0
Dead Coil?
I have had 2 pertronics coils fail me. One oil filled one epoxy.No help from the company whatsoever.Mounted in the stock location,which may have been the problem.The voltage is low at the correct wire. Anyway using the coil that came with the truck when I aquired it,I havn't noticed any change in performance for better or worse. In my opinion just using the pertronics points replacement kit and Fresh tune-up components works very well on stock engined vehicles.
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