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Original69RS-SS 01-15-2022 05:03 AM

Electrical Issues
 
Problem #1: Put my car (original, complete, unrestored, Day2, 69 RS-SS 350/300) away a month ago running great, purring like a kitten as it has for the last 45 years. Tried to start it last week and it started but ran HORRIBLE; it would not run at all w/o foot on the gas. Points were burnt, filed them down, tried a start and it idled unassisted but still ran horrible. Thinking I was on the right track, I replaced the 15-20 year old points, condenser, rotor, and cap. Now it wouldn't start at all. Plugs were really fouled, but I cleaned them and put them back in temporarily. Tried again and it didn't even consider starting. Tested resistance on the the coil which tested marginally OK at 1.5 and 11.77. Set the point gap manually ~.19. Hooked up a timing light to see if I was getting a spark. Nope. ANY GUESSES as to what was happening?

Problem #2: Feel free to call me an idiot, I've been doing it, myself, for the last 3 hours. The last time I messed with the coil I forgot to disconnect the negative battery cable. I noticed a little smoke and realized to my horror that the double wire off the + side of the coil was touching the metal shell of the coil. It was hot and parts of the fiberglass insulation and rubber were crinkled and burnt on one of the wires. I taped it up really good temporarily for one last attempt to see if I could at least get a spark. I rechecked the point gap which was actually little too wide, so I fixed that. Tried to start it and I thought I heard it "try to fire." Tried a 2nd time and I only got one quick metallic "clank" from the starter. Tried a 3rd time and it now does nothing; no cranking, no interior lights, nothing. I see no burnt fuses. Did I fry the ignition harness? Did I re-fry that one damaged wire? Can I replace just the section of the harness from the ignition switch to the coil? Is it time for me to retire from messing with cars? Thanks. Insults gladly accepted.

Too Many Projects 01-15-2022 02:20 PM

The fact that you have nothing from the battery now would lead me in that direction. Trying to diagnose a running issue when the engine won't crank over is a moot point. ASSUMING you have a fully charged battery and/or a charged jump pack, look for a loose/corroded cable at battery and starter terminal and ground. If that all looks good, I would clamp my remote starter button to the starter solenoid terminals to make certain that hasn't failed. If the starter runs, cranking the engine over, with the button, I would suspect the ignition switch may have corroded internally over time and has failed. Have you crawled under the column and looked at that ? It may not show any indication of this, and I'm betting you don't have a "spare" sitting on a shelf, but that would be an easy way to test it, by moving the harness to a test switch and pushing the slide manually. You might be able to "test" your switch by holding your fingers on it and turning the key to start and feel if it gets hot, indicating high resistance. You could pull the harness connector off and look for corrosion on the terminals too.
Ah, forgot, '69 will have a neutral safety switch in the circuit too, which you may want to locate and inspect.


Once you find and correct the issue with the cranking circuit, you can move on to the running issue.

tunes 01-15-2022 03:20 PM

Did you check all the fuseable links on the harness?

bbbentley 01-15-2022 04:26 PM

If you have done a lot of cranking, I have seen the starter get hot enough and, then, repeated cooling between intervals to cause the large nut on solenoid, where battery cable attaches, to loosen.

Original69RS-SS 01-15-2022 04:28 PM

After my last attempt, I've tried nothing, yet. I don't really know what I'm looking for and this old body struggles to crawl up the dash anymore. It's snowing, the garage is cramped and going down into the teens tonight. I just need a focused strategy for when I can get out there again. Now a have a couple of ideas. Thank you gentlemen. One more question, does frying coil wire suggest any damage elsewhere?…like under the dash or in the ignition switch harness?

Too Many Projects 01-15-2022 07:40 PM

Quote:

Originally Posted by Original69RS-SS (Post 1578617)
After my last attempt, I've tried nothing, yet. I don't really know what I'm looking for and this old body struggles to crawl up the dash anymore. It's snowing, the garage is cramped and going down into the teens tonight. I just need a focused strategy for when I can get out there again. Now a have a couple of ideas. Thank you gentlemen. One more question, does frying coil wire suggest any damage elsewhere?…like under the dash or in the ignition switch harness?


Possibly, if the wire casing is bubbled back into the harness tape, it would require unwrapping it far enough back to find the end of the overheat. I doubt it will cause a loss of power with just the jacket meltdown and cool off. Copper wire can stand a LOT of heat and not melt. A soldered joint along the way...it takes very little heat to melt that stuff.
I HOPE you have/had a charger on the battery. If it is drained down to dead, it can freeze, not with temps in the teens, but it won't help it to leave that discharged in a subfreezing temp.
Other than making certain the battery is charged, yeah, wait for warmer weather. I don't know about other people, but for me, problem solving and repairs don't go well when my hands are frozen...:no:

NEATSS 01-15-2022 10:09 PM

Original69RS-SS
1) first start... ran horrible with foot on the gas. Sounds like choke pull off or stuck choke.
2) second start.... ran ruff but idled. Now the choke opened but the plugs are fouled.
3)won't crank.... now there is an electrical issue possible caused by accidently grounding the + lead to the coil.

If you are in St. Louis, MO I am about an hour away. If you want a little help give me a holler.
Dave McCutcheon
Red Bud, IL

firstgenaddict 01-16-2022 08:16 PM

If not mistaken there are 2 fusible links by the starter on the coil ignition harness. One is brown 14 ga and the other I believe is orange 18 or 20 ga.
There is also a resistance wire going to the coil - which provides 7-8 volts AFTER cranking, the wire on a closed loop - points touching - could over heat and melt. This is the reason you see ballast resistors on the firewalls of so many cars - the resistance wire overheated melted and the work around is - ceramic ballast resistor.

Original69RS-SS 01-16-2022 10:28 PM

Thanks all. Will look at everything. Battery is still 100%, so it's not that. I did not do enough cranking to heat up anything, just long enough to hear if any cylinders would fire. There is no corrosion anywhere on this car but I'll double check on that, too. I'll look to see if fusible links are burnt out. I'm hoping that one wire only melted a little bit and just that one can be repaired. I'd hate to have to rewire the car. The plugs are wet and gritty with carbon. I'm betting the electronics is probably part of that and has been sending a weak spark. One is VERY oil soaked so I know what that means. Grrr. The time I drove it before this it ran PERFECTLY. Unbelievable for a 52-year-old un-rebuilt engine. (Though I did do a valve job on it 45 years—and 35,000 miles—ago and a timing chain about 10.)

Original69RS-SS 01-22-2022 06:05 PM

Thanks for your help.
 
Car did crank over. It may have been the battery after all, sorry. Never showed any symptoms of slowing down, hard to believe, but I re-taped the bubbled + coil wire , charged it, replaced the 3A IGN fuse in the fuse block (looked bad with a lot of junk floating around inside the tube, but it did have continuity.) And it did crank. So problem #1 seems OK. No idea if I have a spark yet—Problem #2. Will try that again when I get home a little later. I know bad plugs put strain on the coil, but the Ohm test on the coil seemed at least marginally OK at 1.5 positive to negative, and 11.77 center pole to negative. Anything else I should check, coil-wise? Is there anything else that would be suspect in getting no spark at all? Could gas-fouled plugs alone cause no spark at all? Thank you, all.


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