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Intermittent tripping of charging system breaker(fusable link)

JoshIms

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I have a 1969 superbee with a 383. Bought car with Mopar electronic ignition but still running the original charging system. Upgraded to a dual field 95 amp alternator and post 70 voltage regulator setup. Ran this way for a year with no issues. Was informed at that point that the factory bulked connector and amemetter where at serious risk of overloading. Found a great artilcle reguarding bypassing of ammeter getting rid of spade connectors and running solid wire through the bulked connector and connecting both sides of that circuit to the starter relay through a fusable llink to power the dash and lights. Then sending a larger wire directly from the alternator to the starter relay with a 200 amp breaker in line. All wiring changes where heatshiriked soldered and or cleanly crimped eyelet connectors. Now breaker intermittently gets tripped stopping the charge to the battery. Seems like it happens a lot more at night with head lights on. Doesn’t trip when turning them on or hitting brakes or when electric fans kick on just randomly during driving conditions. I do not have a good education of electrical theory I kind of get it but just enough to get me in trouble I guess. Looking for advice on where to start.
 
Guessing that you have weak connection somewhere in your wiring. Check it all over again, good clean connections!
 
What wires/system are your crimped eyelet connectors feeding? Anything crimped is marginal at best.....
 
200 amps is a lot. Maybe just a bad breaker? Could throw a 150 amp fuse in the circuit and see if it actually pops before the breaker but even if it does I would think it's an intermittent short.
 
Do you have a breaker to replace the fusable link or is there still a fusable link in the system?
 
Do you have a breaker to replace the fusable link or is there still a fusable link in the system?
Sounds like he kept the fusible link in the main supply into the interior of the car from the starter but added the breaker on the supply side of the entire system being fed by the alternator.

No way that alternator is supplying over 200 amps or that cars electrical system is demanding the same without a short circuit or weak breaker is my guess.
 
I have a 1969 superbee with a 383. Bought car with Mopar electronic ignition but still running the original charging system. Upgraded to a dual field 95 amp alternator and post 70 voltage regulator setup. Ran this way for a year with no issues. Was informed at that point that the factory bulked connector and amemetter where at serious risk of overloading. Found a great artilcle reguarding bypassing of ammeter getting rid of spade connectors and running solid wire through the bulked connector and connecting both sides of that circuit to the starter relay through a fusable llink to power the dash and lights. Then sending a larger wire directly from the alternator to the starter relay with a 200 amp breaker in line. All wiring changes where heatshiriked soldered and or cleanly crimped eyelet connectors. Now breaker intermittently gets tripped stopping the charge to the battery. Seems like it happens a lot more at night with head lights on. Doesn’t trip when turning them on or hitting brakes or when electric fans kick on just randomly during driving conditions. I do not have a good education of electrical theory I kind of get it but just enough to get me in trouble I guess. Looking for advice on where to start.
I would eyeball every inch of that supply wire from after the circuit breaker over to the the starter relay connection to check for chaffing or breaks in the insulation to bare metal of the vehicle causing a short circuit. Otherwise maybe swap out the breaker itself or install a slightly undersize fuse in the same circuit to confirm an actual excessive current draw or just a weak breaker. Hope this helps
 
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All good advice.....my money is on a wire that's worn bare touching something every now & then.
 
Thanks guys I will look it all over again wire is all brand new high quality wire. Correct fusable link protecting wiring into dash area and breaker for main feed from alternator. Crimped eyelets at alternator and starter relay crimped soldered and double heat shrinked. Will look for damage to any new wire.
 
Would the short have to be somewhere between alternator and starter relay or could it be anywhere? Battery to starter relay? Relay to starter? If the alternator wasn’t grounding through it’s case to the motor well could this cause the problem?
 
Would the short have to be somewhere between alternator and starter relay or could it be anywhere? Battery to starter relay? Relay to starter? If the alternator wasn’t grounding through it’s case to the motor well could this cause the problem?
200 amps is a bunch of current. I am guessing the fusible link you installed is rated for quite a bit less than the breaker? So the link would likely pop if the load(or short) was too high anywhere after that fusible link.
Assuming the fusible link is indeed a lower rating, I would look between the breaker and the fusible link or any circuits that are protected by that breaker that may T off before the link. It's hard to know exactly where to start since we aren't really sure how these circuits have been installed.
I would do a quick visual of that circuit and then suspect that breaker. They are mechanical parts that can be less reliable than an actual fuse.
 
I would suspect the circuit breaker? 200 Amps is alot and the only way you would normally see that much flow is being sourced from the battery to a short circuit to ground.
 
I would suspect the circuit breaker? 200 Amps is alot and the only way you would normally see that much flow is being sourced from the battery to a short circuit to ground.
Going to get rid of it and install a fusable link and see what happens thanks
 
JMO. If it's tripping the breaker, the breaker may be bad. OR, there is a serious short somewhere that is spiking the system. A fusible link will just allow the short to continue to burn in the system.

I would check everything in the headlight circuit if it only trips when lights are on.
 
JMO as well. A 200 amp breaker is way to high of a rating. 20% over max expected/potnetial amperage would be good, so a 120 amp breaker is what I would run.
 
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