The grounding "daisy chain" is a pair of black 18 gauge (or less) wires that loop from the steering tube mount (base ground) and move left or right. Simple crimp connectors mount under the instrument mounting nuts.
I'm sure I can find a spare original one in my boxes o' bits... there is one crimp connector substantially larger than the rest. This fits under the outboard 1/4-28 bolt that retains the dash extension (from interior bulkhead to dash) on the LH side. if you are running a clock and an ammeter (or voltmeter) you'll need to add a jumper as these were not accounted for in the original assembly
Can you use the same daisy chain which links 4 gauges ( including an ammeter) also to the cigarette lighter ground air using 18 gauge wire ?
I'll send you a pic of the original tomorrow
I once noted that the dash lights dimmed when the cigar lighter was used. Ever since then, I've given it a dedicated separate larger ground wire (16 gauge). Just sayin'
That was my thought as well, to use a heavier gauge wire. Is the cigar lighter powered by that purple wire near the glove box and I think that wire is fused ? Thanks
If the circuits are as original, yes the purple is fused.
same circuit as the horns...
That is sound advice I will definitely put an inline fuse to the fuel pump which by looks of things it is hooked up before the two 35 amp fuses What amperage fuses would you recommend on both the fuel pump and cigar lighter ?
I will go with 5 amps. Thanks
Originally purple wires would have been a 50amp fuse... which is miss-rated as they were actually a 25 amp fuse (same as horns). The fuel pump will draw a lot more than 5 amps. White wires are typically unfused, but sit on the opposite side of a 30 amp fuse for the green wires. (wipers, gauges, heater) Lucas 30 amp fuses were actually rated at 17amps. Lights were not fused. On Jaguars they are, on a 30 amp fuse. if you want to take the load off of the switch, you could always run the main and high beams through a relay.
I use facet pumps from Pegasus Racing. They carry several different facet pumps ranging from 2 to 4 PSI up to 7 to 10 PSI. They all pull roughly 1 amp. An SU pump will pull in the range of 5 to 6 amps so with the facet pump the 5 amp fuse doesn't present a problem for me but the original pump pulling 6 amps would require a slightly higher amp fuse. As far as the lighter goes I guess you would need to know how many amps a phone charger or Garmin will pull. If you look at the corner of the bulkhead just above the voltage regulator in this photo you'll see the main Alpine