Hey now, how is everyone??? I pulled ol yeller out for a spin, and the ammeter is leaning towards the "C", I was worried about over charging. Usually it sits right in the center, it has moved to the next line on the gage. I hooked up a meter, and it's showing about 13.2-13.6 VDC, so it seems I am o.k.?? Could this be a sign of the ammeter going bad?? Voltage regulator bad?? thanks everyone.....Lenny
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My ammeter is straying a bit.....
- Thread starter lleno
- Start date
AzPete
Well-Known Member
The slightest change will cause major movement in the stock amp gauge. Check all your connections, including the grounds. You battery and alt. sound ok based on those numbers listed.
+1. Midlife has the same problem, and as master Electrician/Shorts Checker, I still haven't found what is going on. At times, the ammeter gauge goes to higher readings than normal, yet everything checks out. We're dealing with two parallel circuits with resistance differences on the order of tenths of ohms, something that requires expensive equipment to measure accurately. I believe my problem is in the molded connector from the alternator to the starter solenoid and at the solenoid. The connection inside has a tiny variation of resistance due to crimping that I cannot get to, and that variation is reflected in the ammeter gauge.
With 2 years of harness restoration work behind me, there's about 30% failure rate of connectors inside a molded plug. My experience suggests the failure mode as described above; very few people have that level of experience with Ford wiring to even consider that possibility.
With 2 years of harness restoration work behind me, there's about 30% failure rate of connectors inside a molded plug. My experience suggests the failure mode as described above; very few people have that level of experience with Ford wiring to even consider that possibility.
apollard
Active Member
Mid is right - I redid my harness to eliminate the connectors when I upgraded to a 3G. At the same time, I upgraded the wiring. The wire from the alt to the starter solenoid is used as a shunt for the amp meter, so I had to know what resistance it was. No way to measure it (that I have access to anyway). BUT, the wire is was ~ 3 ft long IIRC, and the resistance calculated out to 0.00299 ohms. I then checked this with the voltmeter (pull 30 amps across it and you can measure the volt drop across it fairly well). I could never get consistent readings, every time I moved the wire it jumped around. Bad connectors - took them out, soldered it together, and confirmed my calculation was pretty close. I ended up using 2 x 10ga wires six feet long as the shunt.
FWIW, my connectors, wires and the splice in the power feed all were partially melted when you looked close. Some you didn't need to look so close - the wires at the splice had melted insulation 3-4 away from the actual splice. The power feed to the switch / under dash measured out as only 12 ga! Easy to see why these older cars would burn up sometimes.
FWIW, my connectors, wires and the splice in the power feed all were partially melted when you looked close. Some you didn't need to look so close - the wires at the splice had melted insulation 3-4 away from the actual splice. The power feed to the switch / under dash measured out as only 12 ga! Easy to see why these older cars would burn up sometimes.
Makes a lot of sense......I did change two of the underhoood harnesses[I believe I asked Mid some questions about the differant brands]I stilll have to change the one that runs to the headlights.....So I guess I'll check with my meter for a while,I also want to install some aftermarket gauges.....\\