[Megunticook]

OK, I'm pigheaded enough to have kept my factory ammeter setup (after rewiring everything from scratch to ensure it's all clean and tight), but I'm installing a voltmeter now, too--mainly because I've had a couple voltage regulators go out on me in the past few years, and a voltmeter would alert me to that condition instantly (whereas with the ammeter I had to do more troubleshooting).

Plus I just like installing frivolous stuff in my spare (ha!) time.

Anyway, I was wondering a few things:

1. Does the hot wire to the vm need a fuse?
   
2. Where's the best place to tap into the electrical system? I have a handy, unused wire under the dash I labelled "IGN ACC" a couple years back which, if memory serves, is connected to one side of the fuse box bus (I had taped off the end, labeled it, and left it tied up out of the way about where the radio is, I think I was thinking that would power a radio/CD player someday...should've taken better notes!)
   
3. Where's the best place for the vm's ground wire to terminate? I was thinking one of the voltage regulator mounting bolts, since the VR body has a nice shiny new braided strap to the block, which the alternator is grounded to. I have the wire all in place, just need to install a ring terminal, but thought I'd check in with the electrical Einsteins here first...

 

[Megunticook]

OK, I think I just figured out the answer to the first 2 questions--the wire I labelled 'IGN ACC' that runs from the fusebox must lead to the "Ignition Accessory" fuse in the box, right between the horn and heater fuses. And there's a 20A fuse in there.

That's apparently where a factory voltmeter is installed.

I have that right?

 

[bherder]

Any 'good' ground is a GOOD ground.
Wire it up (ACC in the fuse box is fine) so it's only on when the ignition is on.
It's pretty bullet-proof....

 

[Megunticook]

Any 'good' ground is a GOOD ground.
Wire it up (ACC in the fuse box is fine) so it's only on when the ignition is on.
It's pretty bullet-proof....

I presume you have a vm since you did the ammeter bypass. Where do your leads terminate?

 

[Delray Dude]

Any 'good' ground is a GOOD ground.
Wire it up (ACC in the fuse box is fine) so it's only on when the ignition is on.
It's pretty bullet-proof....

What he said.

I tapped my voltmeter guage off the lead to the (non-exhistant at the moment) stereo power lead and a good ground under the dash (actually one of the bolts that secure the guage to the metal part of the dash). Works great.

 

[1972-D100]

Hey Ed, I think you are over thinking this one. As long as the VM gets a good source power wire, and a good ground you will be golden. I have mine wired off of the cigarette lighter wires, I used both the ground ad the hot, works great. The way you were planning on wiring will work as well, it is up to you and how much wire you want to run, I looked for the closes thing and I didn't want to go through the firewall unless I had to. Oh yea I have your fenders ready to be shipped to you.

Ron

 

[Megunticook]

Hey Ed, I think you are over thinking this one.

I have that tendency, don't I? Well, I went ahead and wired it up as described, hot to the "IGN ACC" wire off the fusebox and ground through an existing firewall grommet out to the voltage regulator. Overkill, I know, but what the heck.

I was all set to wrap things up, turned the lights on to make sure the gauge light worked. Nope. Tested the light leads with a voltmeter, 11+ volts there. Hmmm...grabbed a spare lamp assembly (I have a couple unused gauges from the same company, tried that, no light. What the hell? Checked the leads again, tried a different voltmeter just for kicks, it's definitely got juice.

All I can think is I got 2 "made in Taiwan" bulbs that are bad. But pretty weird. I have another extra, will try that. Why do these simple tasks always turn into a big hassle?

Oh yea I have your fenders ready to be shipped to you.

I submitted my account application to Greyhound last week, still haven't heard back. I'll see if I can get ahold of them this afternoon. Thanks for your patience.

 

[1972-D100]

Two bad bulbs at the same time, I guess it could happen, but what are the odds???? Is the ground connection good on the light assembly?

 

[Megunticook]

I know, it seems unlikely.

Hard to know about the ground connection on the bulb, it comes sealed in a grommet with the leads already attached:

The second one I tried lit right up for a second at first but then I couldn't get it to light again. WTF?

I'll test the light on the bench with a 12v source I guess...

 

[1972-D100]

Thats what I would try, it sounds like there is either a bad ground in the light itself or maybe its corroded inside or something along those lines....

 

[bherder]

I know, it seems unlikely.

Hard to know about the ground connection on the bulb, it comes sealed in a grommet with the leads already attached:
The second one I tried lit right up for a second at first but then I couldn't get it to light again. WTF?

I'll test the light on the bench with a 12v source I guess...

Yeah, must be the 'Made in (Insert non-USA Name Here)' thing....
Just like my brand new BUSS fuse holder that charred itself, while the fuse was just fine.
Does it have one of those (Like the instrument lights .. 191's I think) little bulbs with the wire wraped over the base of the bulb? Sometimes ya gotta bend that little wire out a bit.
I know what ya mean though Ed.... You have something BRAND NEW in hand, but ya gatta' FIX the damn thing first to get it to work. Drives me freekin' nuts sometimes.

 

[Megunticook]

Took a sec. at lunchtime to test those lights, the "new" one was DOA. The original one I had in there appeared to be DOA also but upon further inspection I found it had pulled loose from a crimped/soldered/shrinktubed connection I'd made on it--I think I must've yanked on it at some point during the install. Those 20 gauge wires only have a few strands, hard to get a good solid crimp on them sometimes.

Anyway, I've got it all working now.

But that brand new bulb was definitely dead as a doornail...

 

[bherder]

Well, guess we can't blame this one on 'Charlie' then ....

 

[charlie1935]

Hey! Don't take my name in vain! :gr_patrio

 

[Megunticook]

Say, tonight when I plowed the road was the first time I ran the truck with the voltmeter installed. I noticed at idle with the highbeams on (fan and wipers off) it read just a tad over 13v. This is a little on the low side compared to the FSM specs., but then again they say you should have all the accessories off and the motor running at 1250 RPM. So I suppose I'm right about where I need to be.

Sure is nice having all these gauges...nice to be able to keep a watchful eye on all the key systems. Still like having that ammeter alive.

Looks like my stock water temp. gauge needs to be rewired--guessing there's some resistance there (it's hanging on by a few copper strands at the terminal). At 190 degrees the needle is just into the "normal" range. Seems to me it should be reading right in the middle area, or possibly a little higher.