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Stock battery ground

adam05ford

Full Member
Joined
Aug 29, 2010
Messages
185
Loc.
San Marcos, Texas
Where is the stock battery ground location. The bronco i just bought didn't have any battery cables and i just wasn't sure exactly where the stock ground cable ran. (frame,body,block)?

Thanks,

Adam
 

Vragor

Jr. Member
Joined
Jul 22, 2010
Messages
149
Loc.
Colorado Springs
Mine is on the front end of the passenger side head. Several bolt holes on there. Just be sure to clean it real good so you get good contact
 

Steve83

Bronco Guru
Joined
Jul 16, 2003
Messages
9,359
Loc.
Memphis, TN, USA, Earth, Milky Way
Ideally, get a black wire long enough to go from the battery to the engine and then to the frame, with a smaller wire at the battery clamp that can be connected to the core support. Strip some insulation midway to solder on a tab to attach to the engine so the cable is continuous from the battery to the frame. Or it can go to the frame first & then continue to the engine.

I recently added another from the battery directly to the alternator.

To make your own cables, read these captions:

 

70_Steve

Old Guy
Joined
Dec 13, 2002
Messages
8,317
For sure, the engine, body and frame all have to be grounded. You should make the engine block the main source for all grounds by connecting the negative battery cable to it. The largest current drain on the Bronco is the starter motor, which is grounded to the block.

Not sure, as Steve83 suggested, that it's necessary to have that heavy of a ground cable to the frame. On a stock Bronco, the only thing that grounds to the frame is the fuel level sending unit. But, it certainly won't hurt.

On my Bronco, I have the negative battery cable bolted to the block at a threaded hole behind the alternator. I have the body grounded using a braided ground strap (Help section of auto parts store) bolted to the rear of the intake manifold and to the firewall. I also have another ground strap bolted to the block at the same point as the negative battery cable, and running over to the frame.
 

Steve83

Bronco Guru
Joined
Jul 16, 2003
Messages
9,359
Loc.
Memphis, TN, USA, Earth, Milky Way
Not sure, as Steve83 suggested, that it's necessary to have that heavy of a ground cable to the frame. On a stock Bronco, the only thing that grounds to the frame is the fuel level sending unit. But, it certainly won't hurt.
It's just redundant on a stock truck, but it's good to know you have it if you ever install a winch. My used 12K didn't come with a dedicated ground cable, but it still works because my frame is grounded the way I described. It's also good if you have amplifiers, or an aux battery in the back, or a hitch-mounted winch, or a trailer with 12V devices on-board...
 

Steve

Bronco Guru
Joined
May 5, 2003
Messages
2,986
Loc.
Grand Junction, CO
It's just redundant on a stock truck, but it's good to know you have it if you ever install a winch. My used 12K didn't come with a dedicated ground cable, but it still works because my frame is grounded the way I described.

A winch that's grounded to the frame, without a cable to the battery negative post? I don't think I'd trust such a setup with the current that a winch can draw.
 

70_Steve

Old Guy
Joined
Dec 13, 2002
Messages
8,317
It's just redundant on a stock truck, but it's good to know you have it if you ever install a winch. My used 12K didn't come with a dedicated ground cable, but it still works because my frame is grounded the way I described. It's also good if you have amplifiers, or an aux battery in the back, or a hitch-mounted winch, or a trailer with 12V devices on-board...
When I first got my Bronco, I was redoing the grounds, and installed a huge braided ground strap from the block to the frame, anticipating installing a winch, and assuming that they grounded through the frame. Then I get my winch and it's got a seperate ground cable!:p But, as you mentioned, I'm glad I installed that big frame ground, just in case I ever need it.
 

DirtDonk

Contributor
Bronco Guru
Joined
Nov 3, 2003
Messages
51,619
All of the above. EB's didn't really come with enough grounds to begin with. They had just what they needed when everything was new and in perfect shape, but nothing more.

Stock on the earlier years and probably all (at least up to '72), Ford had the single negative cable doing both the body and the engine. On it's way down to the engine block, there was a bare section with a metal clamp soldered into position with a tab that bolted to the inner fender. You can probably still find the screw, or at least the hole, near the upper front corner of the inner sheetmetal. Just behind the battery and facing the exhaust manifold. Right around the corner from the starter solenoid/relay.

And the closer you can get the engine side to the starter, the better. Not that current won't flow from the front of the block to the rear, but if you have the option of getting it closer to the starter motor to begin with, the better I think.

Paul
 

Broncobowsher

Total hack
Joined
Jun 4, 2002
Messages
37,073
Many of the replacment battery cables will have 1 larger cable and 1 or 2 smaller wires.
Big cable goes to the engine, typically the front of the passenger cylinder head. The reason is the big current stuff is between the engine and the battery, namely the starter and alternater.
The smaller wires are best run to the body (the screw holding down the voltage regulater is an excelent spot as it gives the regulater an accurate ground reference to the battery) and if you have a third wire, the frame.
If you are running a frame grounded winch (old bellview for example) run a seperate heavy ground to the frame. Either off the head next to the battery cable of off the battery itself.

Now tossing a on a few spare grounds here and there (those light little braided ground straps) is always a good idea. Back of the intake to the firewall is a good one. Off the alternator case to an inner fender is also nice. If you have EFI, an exhaust to body halfway down the exhaust can help the O2s read a little better.
 

Steve83

Bronco Guru
Joined
Jul 16, 2003
Messages
9,359
Loc.
Memphis, TN, USA, Earth, Milky Way
A winch that's grounded to the frame, without a cable to the battery negative post? I don't think I'd trust such a setup with the current that a winch can draw.
Actually, it only grounds through its case to the (powdercoated) bumper, which is bolted to the frame. I agree that it's not ideal, and as soon as I have the slightest problem, I'll add a direct ground from the winch to the battery. But so far, no problems. And what's the worst that could happen? The winch bogs down & a puff of smoke comes out between the bumper & frame where the powdercoat gets hot? I can handle that. I carry jumper cables, a come-along, & plenty of recovery tackle. ;D

 
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