voltage regulator / grounding

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goat_72
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voltage regulator / grounding

Post by goat_72 »

I have been inspecting my trucks electrics as a result of troubleshooting instrument panel gauges, fuel tank sending units etc. I noticed out of the electrical components my voltage regulator seems to be original or at least resembling that of a 45-year-old car. I have two questions.

1. On the voltage regulator, there seems to be a black cable / red stripe that acts as a ground for something. my research & inspection tells me it is for the alternator. The cable is in very poor shape, see pic. If I use a multimeter with red on positive battery terminal and black on the alternator / regulator grounding or exposed cable I get a 12v reading as one would expect. however, on the terminal, the voltage is a bit irregular suspect due to the integrity of the wire. if I put it on the exposed wire it is a solid 12 v.

a. Is my assumption correct with respect to it being an alternator grounding (solid black w/ red stripe)?
b. What sort of problems or effect would I have with the cable that is not integral?

2. whoever worked on the truck used insulation tape every to re-harness the cables. Any products such as cable trunking people have had success with in restoring electrics. I am good with cat 5 / data center cabling, perhaps a bit OCD, this crows nest is driving me crazy.
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'72 f100 swb
'17 audi allroad
'15 toyota highlander
wife & 2 kids
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sargentrs
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Re: voltage regulator / grounding

Post by sargentrs »

You can use this diagram for a reference. http://www.fordification.com/tech/wirin ... _quick.jpg Yes, that is a ground. If not properly grounded, the voltage regulator and alternator will not function correctly. The voltage regulator requires a good ground connection through its housing to the radiator support. Make sure the mating surfaces are clean all bolts/screws are tight so that the VR does not "wiggle". I like to use bolts, lock nuts and star washers on all contact points. For my electrical connections and splices I prefer to use uninsulated connectors, solder and heat shrink tubing.
Randy
1970 F100 Sport Custom Limited LWB, 302cid, 3 on the tree. NO A/C, NO P/S, NO P/B. Currently in 1000 pcs while rebuilding. Project thread: http://www.fordification.com/forum/view ... 22&t=59995 Plan: 351w, C4, LSD, pwr front disc, p/s, a/c, bucket seats, new interior and paint.
1987 F-150 XLT Lariat, 5.0/C6 auto.
goat_72
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Re: voltage regulator / grounding

Post by goat_72 »

I replaced the grounding cable or section of it that was in very poor shape. I now get a solid 14 volts to the battery when the engine is running.

I struggled to find a replacement OEM like alternator wiring harness for 72 f100, it wasn't clear if a wiring harness was solid with said new alternator. (Where it is not too cost prohibitive, I am systematically trying to replace vs. repair.)
'72 f100 swb
'17 audi allroad
'15 toyota highlander
wife & 2 kids
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sargentrs
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Re: voltage regulator / grounding

Post by sargentrs »

I believe this might work on our trucks too. http://www.mustangsunlimited.com/Mustan ... ustang.axd

And Summit says this one fits almost every model between 1965-1980. https://www.summitracing.com/parts/rnb- ... plications
Randy
1970 F100 Sport Custom Limited LWB, 302cid, 3 on the tree. NO A/C, NO P/S, NO P/B. Currently in 1000 pcs while rebuilding. Project thread: http://www.fordification.com/forum/view ... 22&t=59995 Plan: 351w, C4, LSD, pwr front disc, p/s, a/c, bucket seats, new interior and paint.
1987 F-150 XLT Lariat, 5.0/C6 auto.
gritlight
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Re: voltage regulator / grounding

Post by gritlight »

I just burned up the grounding wire as pointed to. Mine goes directly to the alternator and connects with that black ruber thing. Any ideas on replacing that wire set?
71Fe2O3
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Re: voltage regulator / grounding

Post by 71Fe2O3 »

Dennis Carpenter has an alternator wiring set:
http://dennis-carpenter.com/alternator- ... z-14305-a/
and also a voltage regulator wire set and plug:
http://dennis-carpenter.com/voltage-reg ... -10316-rp/
Fred

1970 F100 4WD short bed, 360 engine, very rusty plow and yard truck

1971 F100 2WD long bed, 302 engine, on the road

1968 F100 2WD long bed, 360 engine, stripping for parts
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