Top End Miss
OK, IF I understand what you did and what happened.......................please correct me if I'm wrong.
The fact that running a direct line from the battery to the regulator "cured" the problem indicates that you DO have voltage drop in the ignition harness. Visualize in your mind the path (stock wiring)
Battery -- fuse link -- bulkhead connector -- ammeter circuit -- ignition switch connector -- through the switch -- back out the switch connector on dark blue "run" line -- back out the bulkhead connector -- to the ignition system, the regulator "I" terminal, and the alternator field on 70/ later isolated field systems.
ALSO in this mix is the alternator output line which goes
alternator -- bulkhead connector -- other side of ammeter -- through ammeter -- and thus "tees" into the harness section mentioned formerly.
ANY bad connection or drop in this area can cause this surge. In rare cases, surge can be caused by what amounts to R.F. interference from something like a high power ignition system, which can produce noise on the 12V buss and interfere.
But.....I'm betting on a bad connection. IF you cannot resolve a possible bad connection in the bulkhead, or the igntion switch/ switch connector, I'd get a good heavy relay and install in the engine bay
Feed one contact with power off the starter relay stud, and the output contact feeds the ignition system, regulator, and alternator field.
Your "blue run" wire will now go to the coil of the relay, and the other coil can get grounded.
Also, instead of grounding the relay coil directly, you can ALSO run the ground side coil back inside the car to a toggle switch hidden somewhere, and create an anti theft device.
If, for example, you use a Bosch relay, here:
30 -power coming in from starter relay battery stud
87 new "run" output feeds power out to ignition, alternator field, regulator "I" terminal
86 hook your old blue "run" wire here to energize relay with key in run
85 ground this, or run to a hidden toggle to ground for anti theft
Another way, if you are planning on running electric fans, fuel pumps, other heavy draws, is to use a "continuous duty solenoid" like this:
These look sort of like a starter solenoid and ARE NOT. You can NOT use a starter solenoid, which are designed only for "intermittent" use, not "continuous" use. Any "good" parts store should have 'em.
In this case, one big stud hooks to the big battery stud on the start relay
The other large stud is the power output in "run" goes to regulator, ignition system
One small stud goes to old blue "run" wire
Other small stud is grounded, or as with Bosch, run to hidden "anti theft" switch.
OK, IF I understand what you did and what happened.......................please correct me if I'm wrong.
The fact that running a direct line from the battery to the regulator "cured" the problem indicates that you DO have voltage drop in the ignition harness. Visualize in your mind the path (stock wiring)
Battery -- fuse link -- bulkhead connector -- ammeter circuit -- ignition switch connector -- through the switch -- back out the switch connector on dark blue "run" line -- back out the bulkhead connector -- to the ignition system, the regulator "I" terminal, and the alternator field on 70/ later isolated field systems.
ALSO in this mix is the alternator output line which goes
alternator -- bulkhead connector -- other side of ammeter -- through ammeter -- and thus "tees" into the harness section mentioned formerly.
ANY bad connection or drop in this area can cause this surge. In rare cases, surge can be caused by what amounts to R.F. interference from something like a high power ignition system, which can produce noise on the 12V buss and interfere.
But.....I'm betting on a bad connection. IF you cannot resolve a possible bad connection in the bulkhead, or the igntion switch/ switch connector, I'd get a good heavy relay and install in the engine bay
Feed one contact with power off the starter relay stud, and the output contact feeds the ignition system, regulator, and alternator field.
Your "blue run" wire will now go to the coil of the relay, and the other coil can get grounded.
Also, instead of grounding the relay coil directly, you can ALSO run the ground side coil back inside the car to a toggle switch hidden somewhere, and create an anti theft device.
If, for example, you use a Bosch relay, here:
30 -power coming in from starter relay battery stud
87 new "run" output feeds power out to ignition, alternator field, regulator "I" terminal
86 hook your old blue "run" wire here to energize relay with key in run
85 ground this, or run to a hidden toggle to ground for anti theft
Another way, if you are planning on running electric fans, fuel pumps, other heavy draws, is to use a "continuous duty solenoid" like this:
These look sort of like a starter solenoid and ARE NOT. You can NOT use a starter solenoid, which are designed only for "intermittent" use, not "continuous" use. Any "good" parts store should have 'em.
In this case, one big stud hooks to the big battery stud on the start relay
The other large stud is the power output in "run" goes to regulator, ignition system
One small stud goes to old blue "run" wire
Other small stud is grounded, or as with Bosch, run to hidden "anti theft" switch.