I have a couple of braided grounding straps at the house. Would one of those work for battery negative to fender or firewall? I'll have to check once I get home but I believe that blue ground goes back to the starter.
Sorry, been away from the computer for awhile...
Braided straps are great! Just perfect for this. But what size are they?
The typical braided strap you'd see for auxiliary grounds would be one of the smaller type. A pretty small one equals a pretty good size regular cable if I remember.
If they're the big fat 1" thick type that's got a battery lug at one end, you probably won't use it.
Post pics of what you have when you can.
The ground cable going down near the starter motor is also great. It's really kind of a "best practice" even.
But it still looks like it's been there for a long time, so it isn't out of line to think about replacing it even if it still appears to work.
I see you have a quick-disconnect battery lug. You can get a "switch-to-starter" cable as they're often labeled, that has eylets at both ends. One end to the engine near the starter, one end to the quick-disconnect, and done.
I use 2ga as a go-to size nowadays. You can get away with 6ga like Ford did when these things were new, but whenever replacing cables I use 2ga or larger.
But still get at least 4ga and find one the right length that also has the secondary/auxiliary ground wire coming off of it.
I see you also have a body ground there at the battery lug. Or at least it looks like a ground going down behind the battery and presumably to the core support.
This is great too. Maybe just add another one of the same size and run it to the starter relay mounting bolt.
If you have smaller braided straps, or some Black 10ga wire, put one between the back of the engine and the firewall sheet-metal, and the other I’m not sure yet. Maybe between the engine and the frame.
You could kill a couple of birds with one stone while changing battery cables. The new main ground cable can run straight from the battery down to the engine block near the starter motor. where it sounds like yours is now. The secondary ground can go to the starter relay mounting bolt, but you should keep your existing one to the radiator core support.
Haha! Yep, not a problem. I've been using this type of meter (started with analog and now use mostly digital like the one in your link) since I was about five, and still don't know all the functions of these things!
But we can sure check voltage.
Insert the black test lead into the "COM" hole at the bottom of the meter.
Insert the red test lead into the V-upside down horseshoe-ma (volts-ohms-miliamps) hole. (sorry, didn't have time to look up the keystrokes for the symbol for ohms).
Turn the ON/OFF switch to ON.
Turn the dial to the 20v on the DC-Volts scale there on the upper left.
You use the level nearest the one you need, one step above. So if it had a 5v notch and a 20v notch, and a 100v notch, you'd use 20 because the readings will be easy to see and compare to the 12-15 that you're looking for.
Place the red lead on the positive battery stud. Place the black lead tip on the negative battery stud.
The reading in the window will (or should be at least) your precise battery voltage at the moment. Usually somewhere between 12.0 and 12.6 volts while sitting. Maybe up to 13 for a few minutes after it's been running and charging.
With the engine running, do it again and see what the voltage goes up to. Should be in the neighborhood of 14.5v or so.
That's a start at least!
Oh, and the ohms settings on the dial come in very handy sometimes (a lot!) when you're playing around on a Bronco.
Have fun.
Paul
