Voltage drop

Charging, starting, lighting, gauges, HVAC

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Ghill70
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Voltage drop

Post by Ghill70 »

:fr: Hi. I have a 1970 F100. I am wondering what would cause the voltage at the hot-when-on lugs in the fuse panel to be less than 12 volts. I have 12.6 at the battery and 10.2 at those lugs. This is with the truck off. I had an HEI dizzy wired to one of the lugs, it had 12 volts when I installed the dizzy last August. Now, just this week it won't start, and I only have the 10 volts at those lugs. Any suggestions on where to start looking?
Thanks!
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sargentrs
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Re: Voltage drop

Post by sargentrs »

Remove the fuse block and check the connections on the back. Those often get corroded. Also wrap some steel wool around a screwdriver tip and scrub the the fuse contact points.
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.
Ghill70
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Re: Voltage drop

Post by Ghill70 »

sargentrs wrote:Remove the fuse block and check the connections on the back. Those often get corroded. Also wrap some steel wool around a screwdriver tip and scrub the the fuse contact points.
Thank you! I will definitely do all that!
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sparky72
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Re: Voltage drop

Post by sparky72 »

Goes without saying to unplug the battery negative before you go rooting around in the fuse panel with a screwdriver and steel wool :wink:
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Ghill70
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Re: Voltage drop

Post by Ghill70 »

sparky72 wrote:Goes without saying to unplug the battery negative before you go rooting around in the fuse panel with a screwdriver and steel wool :wink:
I had kinda figured as much, but thanks for the concern!
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