Ammeter to Voltmeter replacement 240z

[Graham Palmer]

Hi, this 'old chestnut' again....does anyone have either a voltmeter (that will fit a '73 240z dash ???) ..or an old Ammeter..

Basically I'd like to do the swap...if I cannot find something Original/Datsun that will fit my 240z dash (anyone know what year/model cars would have that ?)

I'd try to find a new Voltmeter that could fit in the dash hole.....so a dead 240 ammeter I could measure and potentially take parts off to get a new voltmeter to fit !...

Does anyone have either a dead Ammeter ?

or a Voltmeter that could be used ?

cheers in advance Graham aka 'Miss Ocotober'

 

[Rob Gaskin]

Just a 'heads up' Graham:

A 260Z/280Z voltmeter is not a straight swap for a 240Z ammeter. I did it in my blue 240 but I did major wiring changes. I suppose you could just join the ammeter cables and insulate them well. Then fit 260Z voltmeter but the housing for the gauge is different due to the different dash angles. I think I used a combination of the two instruments. Also the 'font' is different for the writing.

Personally I would just add a generic voltmeter - then you have the best of both worlds.

However the 260Z voltmeter has a 'charge' light incorporated which of course you don't have in a 240Z. That is a bonus but I was told by an auto electrician (and read in a book) that if the bulb blows you break the 'exciter' ? current in the alternator and it won't charge. However I'm not sure if that is actually the case in our cars. What I was told to do was connect a resister (200 ohm?) across the bulb cct so if the bulb blew you still have a circuit. I did that.

 

[Graham Palmer]

Thanks Rob, I'm leaning towards, disconnecting the Ammeter.. either by joining the two white wires together (and insulating) or running a new wire completely from alternator (now exchanged for internal Vreg) to the fuse board...and somehow isolating the existing white/Ammeter wiring.

btw - to get to the wires/bolts behind the ammeter is that possible with the Dash still in ??...I hope so !

I've also ordered a small digital voltmeter which I may look to 'hide' (in clear sight)...which leaves the Ammeter non working (not a big deal) and a volt meter discretely visible...and addresses ammeter/shunt/fire concerns (hopefully)

G

 

[Rob Gaskin]

Thanks Rob, I'm leaning towards, disconnecting the Ammeter.. either by joining the two white wires together (and insulating) or running a new wire completely from alternator (now exchanged for internal Vreg) to the fuse board...and somehow isolating the existing white/Ammeter wiring.

btw - to get to the wires/bolts behind the ammeter is that possible with the Dash still in ??...I hope so !

I've also ordered a small digital voltmeter which I may look to 'hide' (in clear sight)...which leaves the Ammeter non working (not a big deal) and a volt meter discretely visible...and addresses ammeter/shunt/fire concerns (hopefully)

G

All that seems a huge faff Graham. Yes you can get to the back of the ammeter but you have to remove the heater controls/vent.

I did major dash-wiring work on my 240Z and vowed never to do it again with the dash in situ.

The ammeter is good, ok you'd fit a voltmeter nowadays but unless you want a LOT of work for little gain leave it in and working.

Re the fire hazard, I'd make sure that your wiring is in good condition, fused correctly (including fusable link) and carry a fire extinguisher. Check where the cables come through the bulkhead - good grommet?

Also check your headlight fuses - a common fault is for the fuse holders to overheat and melt the fusebox! Mine had!

 

[Graham Palmer]

Again thanks !..I've done the headlamp relay mod so.. that's taken some of the load out of the system...I'll do as you say..always have the firestick in the glove box.. cheers

 

[Graham Palmer]

I've upgrade the fuse box already with blade fuses

 

[Rob Gaskin]

I've upgrade the fuse box already with blade fuses

I reckon that is a great upgrade.

I've done that on my Honda CB750K

 

[johnymd]

With regard to a voltmeter, I just use a cigarette light usb socket that has a voltage display on it. Its then easy to just glance into the car to check the battery is ok.

 

[Rushingphil]

K.I.S.S.

 

[Fairlineguy]

If you want a volt meter in a 240z in place of the amp meter why not build a hybrid using a 260z volt/fuel gauge?
just need to swap the bezel and bracket them rewire it .
Ive done it with the quarts 260z clock and just flipped a couple of scrap volt and amp gauges over