After a 25 year wait I am finally putting tn a new wiring harness in my 52 and am going to have a problem with the ammeter. New harness is configured for a voltmeter.
1. Does anyone make a voltmeter for the original cluster?
2. If not, has anyone converted the ammeter to a voltmeter?
3. As a last resort, how does one wire the ammeter? Harness is Jegs 20 circuit.
The manufacturers of aftermarket wiring harnesses don't like the liability of running battery charging current through decades-old dash ammeters. Therefore, they encourage people to use a voltmeter instead. There's no danger in using a good condition, properly-wired ammeter, especially if a shunt is used to bypass some of the current around the gauge. The shunt turns the ammeter into a charge/no charge indicator, but even when they were new, dash ammeters were notoriously inaccurate. Jerry
"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt! There is nothing noble in being superior to your fellow man; true nobility is being superior to your former self. - Ernest Hemingway Love your enemies and drive 'em nuts!
Fred, assuming you have the #10405 harness from Jegs, it is really a simple modification to wire the ammeter if you choose that option. And as Jerry indicated there is no danger in using the ammeter if all is in good working condition and with proper wiring technique. Looking at their on-line wiring diagram there is a #16 wire that goes from the fuse panel to the starter solenoid. Just splice the ammeter in series with that wire. Cut it so that one terminal of your ammeter connects to the fuse panel and the other terminal of the ammeter connects on to the starter solenoid. You may find, as I did with my 59, that all is well without a shunt. If the normal operation of your truck seems to peg the ammeter more than you are comfortable with, you can just add the shunt later.
I would also suggest that you include a 14 gage fusible link in that #16 wire near where it connects to the starter solenoid.
I'd suggest replacing that #16 wire with a #10 or maybe a #8, since it will be carrying close to full alternator output on occasion. Use a 60 amp maxi-fuse or a fusible link one size smaller that the main wire in case of a heavy current short circuit. Jerry
"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt! There is nothing noble in being superior to your fellow man; true nobility is being superior to your former self. - Ernest Hemingway Love your enemies and drive 'em nuts!
The #16 wire mentioned is just the numbering system for the wiring diagram, not indicating the wire size. It appears to be permanently part of the fuse panel. The Jegs information does not show the wire sizes and hopefully they are sized correctly.
Fred, that wiring diagram for the "motor group wiring" that Jegs shows on the website has some errors. The alternator and the ignition resistor are not shown correctly. If you are using points ignition the wire labeled "not normally used" should go to the opposite end of the ignition resistor. The alternator wiring is shown correctly on the next page of the online instructions. Be sure that you wire them correctly and not as shown on that diagram.
