I've been thinking about this allot. The engine (68 327) is grounded to the frame and that's it. Should I ground the body and bed (53 Truck) as well? I've looked for references and nothing. Thanks Ken
Yes, the body and bed should be grounded to the frame. Your battery is probably grounded to the body, and you want that ground to have a good connection to the engine/starter/etc.
Seeing as the ground is the "other half" of every electrical circuit you have, it is impossible to have too much grounding. Go ahead and ground every separate body section you have, you'll be glad when you don't run into flickering lights and other erratic electrical problems.
I fixed an issue where I grounded directly to the engine besides the other grounds. Like Gotgas says, you really can't be too safe with too many grounds. Too many parts on these old cars can corrode and affect the ground.
Well, that's not really true. Ground loops can be a BIG problem w/ things like radio reception.. However, It's generally a good idea to make sure that every large piece of metal on the car is grounded, eventually all back to the negative battery terminal. Remember that the bed, bolted to the frame has significant metal to metal contact, and as a result will likely be very well grounded.
After 40 years in the automotive wiring business, I have come up with a list of ways to INSURE GOOD grounds. 1. Run a cable from the battery equal in size to the "POS" cable ("NEG" if a six volt) DIRECTLY TO THE ENGINE BLOCK. (this is especially true if the battery is some distance from the engine) If the battery is in the trunk, INCREASE the GAUGE size of the cables. (both) 2. Using a common wire (I use a 10 gauge to collect the smaller ground wires and terminated at the ground post of the battery) to EACH device - light sockets *** especially - and any other device that requires grounding and run to the ground post of the battery. I normally mount a terminal block at both the front and the rear of the vehicle to gather the grounds from the various devices that need a ground (usually #14 gauge) and connect to the #10 gauge common. 3. A ground strap from the engine to the body. 4. The ignition is grounded by way of the block; UNLESS it's an after-market system that requires it's OWN GROUND; then ground it by way of the 10 gauge ground wire to the post of the battery. (some after-market ignition systems require #12 Gauge ground wires; if it does then change the #10 mentioned above to #12 Gauge) Using this method eliminates the need to "s****e" the paint to bare metal to establish a ground between e.g. - body to fenders. S****ing the paint away these ground points opens up the possibility of corrosion at these locations. *** Light sockets (replacement) are available with a GROUND TAB off the side.
Yeah, running a fat ground lead from the battery to the engine block is the best bet. Then have ground straps between the engine and the body and the engine and frame. If the pickup bed sits on rubber pads, it couldn't hurt to run a ground strap between the bed and the frame. Since it's just a ground for the tail lights and stop and turn lights, something like a 12 gauge wire would be fine as a ground for the bed if you have good clean connections. When you need the most current from your battery is when you're cranking over the engine, so that's why you want a nice fat ground lead going from the the battery to the block. If you go to the frame and then from the frame to the block, there's just more places for trouble with weak corroded connections. Having good grounds will also help save sensitive devices like the modules in Mallory Unilite distributors. I've always been careful to run good ground leads, and I've never blown out a Unilite module in four different cars that I've had Unilites in.
There was an article in a tuner mag, a 350z picked up 5-10 whp with nothing but a bunch of ground straps added. I figure it couldn't hurt.
As long as everything else is properly grounded who's worried about radio reception? I personally like the rumble from my headers!
Instead of battery cable, use same-size welding cable. Welding cable has finer filaments and will carry more amperage.
I'm just saying that over-grounding CAN be a problem, but not one that is likely pertinent to the HAMB.
One thing I learned the hard way. Ground the engine. Never run a ground cable to the transmition. My Dad built a car, put the battery in the trunk, grounded the body and the frame. Then he ran a ground cable to the tailshaft housing of the trans. We took the car to Oklahoma City and drove most of the night. We made it to Topika Ka. and the trans went out. The alternator must have been getting it's ground through the transmition shaft metal seal rings because they all welded themselves to the shafts. Lucky we found a good transmition shop. Now I ground the block, and run a cable to the alternator bracket like GM always did... Jeff
Is there any negative effect (pun intended) when you use a keyed battery connection between the negative battery post and the engine?
You may have a problem with starting, as most of those are not rated for the current required for starting, even though they LOOK like that's where they belong. And, of course, my information may be out of date and there may be a keyed battery connector that IS rated high enough. Cosmo
I've got a '61 vette, and I had to run all grounds to common locations, then to the frame. Even took the motor and put grounds to the frame for things like elec. water pump, etc., etc. If you have an ignition system like MSD, grounds become even more important.
Grounding is a mis-nomenclature as applied to automobiles, but we are all guilty of saying it. In reallity when we connect the Negaitve terminal of the battery to the ch***is or engine block we are making the ch***is the most negative part of the system. When we connect the frame to the engine, to the body, to the bed, or whatever then we are electrically bonding the metals together and placing them all at the same potential. If we were to ground our car we would have to drive a 6 foot conducting rod into the ground and then connect to that rod. But we all know when someone says hook it to ground we know they mean the negative post, but we provide a bond between the metals we want at the same potential.
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