what is a "shunt"

[bloxman]

Walter Moore:

Sorry,

I always fail to remember to include my year of manufacture.

1975 280Z

you said:

"If your shunt is missing, and the car still runs that means that the Ammeter has been by-passed."

Well, I guess your right because the ammeter does not move and the car starts with one bounce of the key.

you said:

If I remember correctly on the later cars it is mounted in the engine compartment somewhere.

That would make a lot of sense , as there are two thin white with red stripe wires, and two large white wires with red stripe attached to a pair of white plastic clips (just as the wireing diagram depicts for the 1975 208Z)

Thanks Walter

[bloxman]

Enigma :

That is a mighty kind offer!

Was it an offer?

I could try and take a decent picture of the connecters if that would be any help.

But I really do suck at photagraphy.

Thanks again

Bloxman

[bloxman]

Hey Tomohawk What's Happening?

So theoretically I could make a shunt, But if I screw it up I'll burn my mostly fiberglass bodied 280 to the ground.

O.K. so maybe I should look for a replacement.

Bloxman

[bloxman]

Zedrally

I have no idea as, I purchased the car with neither the voltage Regulator, (did the Alternator upgrade as a solution to that), nor the shunt.

Bloxman

[bloxman]

sblake01

You said

His car is a 75 280Z which, If I knew where to look on the car for the shunt, I could try to find one for him on my next junkyard trip since I think they have a 75 at the local Pick a Part.

I'm touched you guys(Z car club Members) and You personnally ROCK!

What a kind offer!

The only thing I know about the location is what I posted from the original thread .I copied it from the only relavent thread that the seach found using "shunt".

that menmber said"

on my 75-280 I only have 1 fusible link box, located on the relay bracket.

Underneath this box, is a metal box, 2" x 2" x 6" and it

contains a copper strip, shaped like a "m", and 2 glass

fuses. 2 large gauge wires ( 8ga maybe ) one white and

one white/red connect to the large metal strip, and 2

light gauge wires, same colors, connect to the 2 glass

fuses."

Thanks sblake01

[sblake01]

If you've done the alternator upgrade, you probably should go to the 76-78 voltmeter or, actually, combo volt/fuel meter instead of the 75 amp/fuel meter for the reason V8-240Z gave in post #10. But I'll still be on the lookout for a shunt when I go to the 'yard.

[bloxman]

V8-240Z

You said

"replaced the 45-45 amp meter with a volt meter from a 77-78 280Z. Any of the high output alternator conversions will overload the stock shunt and burn it out like a fuse. The Voltmeter swap was a bolt in.

O.K. so I have done the Alternater conversion already so what are we thinking now that I should remove the ammeter and replace it with a Voltmeter?

Do I join the thicker white with red trace wires together if I do thus are just isolate them?

[bloxman]

If you've done the alternator upgrade, you probably should go to the 76-78 voltmeter or, actually, combo volt/fuel meter instead of the 75 amp/fuel meter for the reason V8-240Z gave in post #10. But I'll still be on the lookout for a shunt when I go to the 'yard.

sblake01

O.K well I'll have to think on all this for a while. Many options (voltmeter, fuel guage ,and /or combinations.

Maybe I'll end up putting new gauges in completely. I mean if I need to know what time it is (the clock) I could look at my watch. That would free up a whole!

So in Summation

the concensus is as I have replaced the Alternator then I would have burned the fuses in the shunt(if I had a shunt) and the Ammeter would have stopped working and I would have had to replace it with a Voltmeter.

So Proceed to step 2 decide on which Voltmeter/ voltmeter/fuel guage i want.

Just a thought...

Will the Factory fuel guage work if the Ammeter is not getting power?

Thanks for continuing to look for the shunt Buddy

Bloxman

[V8-240Z]

V8-240Z

You said

"replaced the 45-45 amp meter with a volt meter from a 77-78 280Z. Any of the high output alternator conversions will overload the stock shunt and burn it out like a fuse. The Voltmeter swap was a bolt in.

O.K. so I have done the Alternater conversion already so what are we thinking now that I should remove the ammeter and replace it with a Voltmeter?

Do I join the thicker white with red trace wires together if I do thus are just isolate them?

That is exactly what I did and then I got the + for the voltmeter from that connection and just grounded the - side. The other way to power the volt meter would be off a circuit that is turned on by the ignition switch.

[=Enigma=]

Enigma :

That is a mighty kind offer!

Was it an offer?

Yes it was, but at the moment, my local JY has only 73, 74 & 81, & 84-89 Zs so no luck there, unless it can be obtained from one of those.

On a seperate note, is it really necessary to replace the ammeter with a voltmeter when swapping in a later internally regulated alternator. We have guys doing this all the time using using only a resistor in line and I have yet to hear of any issues with the older ammeters.

[V8-240Z]

On a seperate note, is it really necessary to replace the ammeter with a voltmeter when swapping in a later internally regulated alternator. We have guys doing this all the time using using only a resistor in line and I have yet to hear of any issues with the older ammeters.

On my 71 that had the 45-45 amp meter the shunt resistor is in the amp meter and I could clearly see where it had over heated by being pushed past the gauge limits. I have my alternator output now going straight to the battery + instead of into the white 10ga wire that is next to the alternator where it used to go. I did this to get the heavy charge loads off the old wiring. I am running a V8 but the charge limits/requirement are really the same since some of the internally regulated alternator upgrades are using the GM alternator. The volt meter is really a better way of montoring the overall battery condition and charge circuit.

[sblake01]

On my 64 320, I converted it from the factory generator to a Ford 60 amp alternator. I fried two aftermarket ammeters before I replaced it with a voltmeter 4 years ago. No problems since. And like Dave says, a voltmeter is a better way to monitor your electrical system. No need to change out the other guages. The 76-79 guage will fit your 75 and look original especially if you use the 76 guage because I think the 77-78 has a different font. Oh, and bloxman, I went to the junkyard this morning but the Z was gone. I'll keep looking. That was just one of 7 'yards that are more or less local.