Strange Thing Happened Today

I went with the Lucas Oil treatment Mike posted as O'Reilly didn't have the Star Brite stuff. I also got the 2 cycle oil with the TC-W3 additive. I put it in the GTO this afternoon and will handle the 300 tomorrow when I take it out.

That is exactly what I am planning to do next driving season, I will add the oil too. I even have a jug of that oil on my shelf for my boat.
 
First of all, a big thank you to saforwardlook(Steve) for spending the day with me troubleshooting my car. As you may or may not have known, my car has been down since these symptoms started. First, I thought it was fuel so Steve and I rebuilt the carb, I checked the pump pushrod, changed the pump and filter, dropped the sending unit and checked my tank liner. None of these fixed my issue. I decided it's got to be Ignition related. I installed Pertronix and it ran like crap; worse than before. I put the points back in and it ran good but still quit after a couple of minutes idling. I replaced the coil, no change. Today, Steve and I bypassed everything and isolated the Distributor and Coil by running a lead from the (+) side of the Coil to the Battery and started it from the Starter Relay with a screwdriver. It ran great and did not quit. We concluded it had to be something between the Ignition Switch and the Coil. We spent a good part of the day troubleshooting the entire Ignition System to no avail. When I was about to give this boat the Viking Funeral down the driveway, I mentioned to Steve Stan's diagnosis of the Fusible Link. He, like everyone else was of the opinion that they either worked or they were burnt. Being as we tried everything else, we gave it a go. I have a spare Fusible Link but the lead that goes to the Horn Relay is too short so I cannot use it permanently but we were able to use it to test. We connected it at the Starter Relay and at the Bulkhead Connector then jumped the lead to the Horn Relay. It fired right up and did not quit. Finally...it runs!

Stan: Take great pride in telling everyone, me included to suck it and you were right. If only I had taken heed to your diagnosis from the beginning it would have saved me a lot of trouble. Good job sir!

Mike: Check your Fusible Link...LOL!
 
I'm going to take a shot at making this myself but I have some questions. In the pic below are the original (Blue Tag) and the new one that is too short to use.





Is the only wire that is Fusible Link wire the larger gauge? I believe the thinner gauge wire provides power to the Horn Relay but is it standard wire or Fusible Link wire? I think it is standard wire. Thoughts?
 
A fusible link is just a special type of fuse designed to protect the wire instead of the device being powered. If there is a dead short, the fusible link will blow before you start melting wires and starting a fire. It will never reset, because it self destructs when it blows. The fusible link ls installed between the starter relay and the battery. Never eliminate it and if replaced never substitute a different size.
 
A fusible link is just a special type of fuse designed to protect the wire instead of the device being powered. If there is a dead short, the fusible link will blow before you start melting wires and starting a fire. It will never reset, because it self destructs when it blows. The fusible link ls installed between the starter relay and the battery. Never eliminate it and if replaced never substitute a different size.

The "take away" from this thread is that while dead shorts will render fusible links forever broken, fusible links can also fail due to electrical/thermal/mechanical cycling over time, causing opens that can reconnect when the electrical load is off, and then open again when the current comes back through them. Stan aptly nailed this failure at the beginning of this thread and explained the fatigue type of failure that Scott has experienced on his 65 300. I will never forget this valuable lesson, and my thanks to Stan for speaking up and saving a lot of frustration in this case.
Steve
 
Think of a fusible link as a light bulb.
When a light bulb goes, it goes. It works or it doesn't.
BUT, have you ever tapped a burnt out bulb and it works (temporarily)?
Same thing...
8852DG18.gif
MOR109.pvw.jpg
 
This discussion is why this forum rocks! Great stuff that is now filed away in the memory banks.
 
First of all, a big thank you to saforwardlook(Steve) for spending the day with me troubleshooting my car. As you may or may not have known, my car has been down since these symptoms started. First, I thought it was fuel so Steve and I rebuilt the carb, I checked the pump pushrod, changed the pump and filter, dropped the sending unit and checked my tank liner. None of these fixed my issue. I decided it's got to be Ignition related. I installed Pertronix and it ran like crap; worse than before. I put the points back in and it ran good but still quit after a couple of minutes idling. I replaced the coil, no change. Today, Steve and I bypassed everything and isolated the Distributor and Coil by running a lead from the (+) side of the Coil to the Battery and started it from the Starter Relay with a screwdriver. It ran great and did not quit. We concluded it had to be something between the Ignition Switch and the Coil. We spent a good part of the day troubleshooting the entire Ignition System to no avail. When I was about to give this boat the Viking Funeral down the driveway, I mentioned to Steve Stan's diagnosis of the Fusible Link. He, like everyone else was of the opinion that they either worked or they were burnt. Being as we tried everything else, we gave it a go. I have a spare Fusible Link but the lead that goes to the Horn Relay is too short so I cannot use it permanently but we were able to use it to test. We connected it at the Starter Relay and at the Bulkhead Connector then jumped the lead to the Horn Relay. It fired right up and did not quit. Finally...it runs!

Stan: Take great pride in telling everyone, me included to suck it and you were right. If only I had taken heed to your diagnosis from the beginning it would have saved me a lot of trouble. Good job sir!

Mike: Check your Fusible Link...LOL!



facepalm.jpg

You DO know that Stan is never gonna let us hear the end of this. . .

facepalm.jpg
 
So it was causing more resistance and cutting the ignition voltage before the ballast resistor thus even less primary voltage to the coil right?
 
The fusible link was apparently closed (complete circuit) when starting the car after a brief time off. Almost as soon as the current started flowing, the link would open up and the car would stall - it took only about 5 - 10 seconds for it to die out. We did see a little low voltage readings before the ballast resistor, and then of course going to zero when the car stopped running. That fact plus Stan's comments pinpointed the problem.
 
Thanks once again Scott, referring me back to your thread. I didn't realize you had been down for so long. I am getting close to 2 months now. I should thank Stan too. :)
 
I'm not going to read this whole thread from the start, but another thing that can happen with electronic ignition is that the ballast resistor can start off with 12v cutting the voltage to 6v, but when the alternator charges over 12v the ballast gets hotter and cuts the outgoing voltage below where the ECU will fire.

I had his happen on my '70 Road Runner; when it warmed up it would die, run, die, run.... Like you were turning the ignition on and off over and over in half second intervals. While it was doing it's seizure thing, I pulled the plug on the voltage regulator and it instantly ran smooth and when I plugged it back in, it started cutting out again within a few seconds.
 
I'm not going to read this whole thread from the start, but another thing that can happen with electronic ignition is that the ballast resistor can start off with 12v cutting the voltage to 6v, but when the alternator charges over 12v the ballast gets hotter and cuts the outgoing voltage below where the ECU will fire.

I had his happen on my '70 Road Runner; when it warmed up it would die, run, die, run.... Like you were turning the ignition on and off over and over in half second intervals. While it was doing it's seizure thing, I pulled the plug on the voltage regulator and it instantly ran smooth and when I plugged it back in, it started cutting out again within a few seconds.

I'm not running Electronic Ignition, it's a stock points system. We tested everything and replaced the Ballast without a change. We changed the Fusible Link and it ran.

The brief time I had the Pertronix installed, I used a Ballast with the guts removed and a wire soldered in place.
 
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I'm not running Electronic Ignition, it's a stock points system. We tested everything and replaced the Ballast without a change. We changed the Fusible Link and it ran.

The brief time I had the Pertronix installed, I used a Ballast with the guts removed and a wire soldered in place.

Yup, I caught that near the top of this page. I just thought if someone else would use your thread for an ignition trouble shooting guide, that I would add my past issue with the ballast and the ECU.

Sorry, didn't mean to stray off subject. :dontknow:
 
Yup, I caught that near the top of this page. I just thought if someone else would use your thread for an ignition trouble shooting guide, that I would add my past issue with the ballast and the ECU.

Sorry, didn't mean to stray off subject. :dontknow:
Usually not a problem but this time you should go to the corner and think about what you've done.
 
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