Simple question: Every article you read relating to wiring it stresses good ( grounds.) I usually go overboard and have numerous grounds throughout the car. I know the ( starter) attaches directly to the block which is already grounded well. Question, should the starter also have a ground strap attached to one of the 2 bolts that hold it on - then to the frame . Or is this overkill ? Gene
It would overkill. Starter bolts should only be used to attach the starter. Block should already have a dedicated ground/bonding cable to the frame/body, no need to add another for just the starter.
But on 6 volt setups I've always run a ground to a starter bolt. Old geezers used to say that years ago.
As said never enough grounds and run a 3/0 to the starter both sides of the battery. I worked on a few glass cars and grounding issues were most of the issues that they had.
I'm thinking that every stock Chevy Adva ce Design truck I ever worked on had woven ground strap from the starter bolt to the frame. Some also had the battery grounded to the frame.
Even though OT vehicles are mostly electrically simple, too many dedicated grounds may create ground loops. If you plan on adding any electronics, be it gauges or tunes, this will affect their operation. Ground loops may become antenna and pickup noise, mostly from Alt/Gen/ignition sources. This will create weird electrical issues. Best is to simply verify your electrical system is up to snuff. Main ground from battery to block. I also like to run a #10 to the inner fender off battery terminal. Older vehicles usually don't have this. Ground bonding jumpers from the engine to hull. Ground bonding jumper from hull to frame. *Some vehicle frames are electrically isolated. Every component then can be immediately bonded/grounded to the hull/frame*. As long as the wiring is correctly sized, connections are clean and tight, you should have no problems. Use proper nut/bolt connection for any sheetmetal ground connection, do not rely on self tapping screws. OEM used those for quick assembly and 'good enough'. External voltage regulators, Ford starter solenoids, anything that needs to be attached to an inner fender works much better bolted rather than screwed.
The starter won't work, or work well without a good ground. Bolting the starter to the block or bellhousing "should" create a ground that is adequate for the job but I have seen starters that wouldn't work and the only problem was corrosion built up between the starter and engine. This condition was created from driving in conditions that most customs and hot rods will never see but it does illustrate that the ground connection is just as important as the power connection. If a good clean mounting surface cannot be maintained, a separate grounding circuit is a good idea.
I read somewhere, that the starter itself gets its ground connection primarily from the flat mating surface flange on the starter to the flat mounting boss on the block, not so much the bolts or connecting hardware that secure it to the block. So it follows that both mounting surfaces should be prepared before installation clean and bright, grind down to bare metal removing any paint & corrosion and tighten securely. A heavy gauge battery ground cable connected directly to block or starter, or near the starter, works well.
Measuring the voltage drop over the ground circuit under load (i.e. when the starter is used) will tell you if it is adequate or not, and take the guessing out of it. As you only have 12 (or 6) volts to start with at the battery (and a couple volts less under heavy load as when the starter runs) any significant voltage loss through the wiring etc. will have a relatively big impact.
This applies only to DC , I mention this in case someone is wiring up their workshop and gets "ground loops" which trip earth leakage protection breakers..
Other the than the battery ground this is the best place for an engine/frame ground to me. Woven tinned copper is the best. Where it attaches to the frame is also where the second one would go to the body. Usually a smaller size woven tinned copper.
Electrical circuitry is completed through a 'common ground'. 'Ground loops'? Those were inadvertent terminated takeoffs resultant in usually left spinouts in tail dragging aircraft.
Ron Francis wire works states you must run a heavy ground cable from the starter area (grounded) back/or too the negative side of the Battery with a "heavy gage cable" Just saying they have been in the business of providing wiring kits for a LONG time.
If the starter mounting is relatively clean and the engine is grounded to the frame or the body and the battery is grounded to the frame or the body adequately then there is no need for a starter ground wire. There are millions of cars and trucks without them
The process in G-son's post, thoughtfully applied while the starter is spinning/cranking the engine, would identify whether a larger cable is needed, which connections need cleaning, which terminal is defective and etc in less time than it takes to drive to the parts store. Also if the battery is up to snuff. No need for a crystal ball or time machine.
Used to be some mfg. that ran a woven ground strap from the starter mount to the frame. I've always done it this way, a woven (battery type) flat strap to a clean bolt surface on the frame. Most motors are mounted with 3 rubber mounts, 2 in front, 1 in the rear. The ground strap guarantees a more than adequate ground.
Lots of different arrangements will work, and they are sort of OK at least when everything is new. The problem is the OEMs were kind of cheap and always used the smallest (and shortest) gauge cables they thought they could get away with. They utilized the frame or firewall too, to save money over copper cable. There's nothing wrong with that except there are two or more electrical connections involved than otherwise would be the case. Any electrical connection is a potential failure point that over time causes high resistance and voltage drop. Just a few hundredths of an ohm will cripple starting, charging, lights, ignition, and accessories. Eventually, it won't even turn over.
Ok, I gonna ask! School me on this “ grounding loop” thing. I have always been in the “ you can not have too many grounds” camp! I my business where I installed high amp draw equipment on new and old trucks I alway added “ dedicated grounds and used the frame most of the time. Some stuff came with ten foot dedicated ground wire not using the frame . I never had any problems with anything. So…..what is this “ ground loop” thing? Bones
Ground loops are a problem in sensitive audio equipment, where you can have several separate units (i.e. the stereo in the dash, an amplifier in the trunk, and so on - or much more equipment in your house). They are connected by signal cables having signal wires at the center and a grounded shield around it to keep noise from the surroundings out. If the different units aren't grounded exactly equally the ground voltage may be slightly different, making the signal cable shields carry a lot of current between units, possibly causing audio problems or damage. There are ways to insulate the signal grounds from each other to prevent this. But that's sensitive stuff that has to be interconnected. I fail to see how unsensitive automotive systems that don't really interconnect would have any such problems. At least not before you have a very real voltage loss problem somewhere due to bad connections.
Well things have changed over the years, as mentioned before, Chevy did run the braided strap starter to frame. But that wasn’t to ground the starter, that was to ensure the frame was a ground bus. The engine blocks were always the source ground for the starter. Batter - to the block. Those were the only two grounds I can recall on the ‘55-9 Chevy pickups I had. Later on in years I never saw a ground cable at the starter. Still to the engine, engine to firewall a some time the hood. The firewall was the body ground for lights etc. my opinion, just mine, is that a few good, proper grounds is all that is needed, distributing a bunch more is just a waste of wire to me.
One detail to keep in mind is which parts in the electrical system run off the battery, and which (practically) don't. Yes, they're all hooked up to the battery, but the battery isn't all that involved in using most of them while driving down the road. The starter clearly runs off the battery, as the battery is the only available power source at the time you use the starter. But then the motor starts, the generator/alternator starts supplying power, and as long as you don't use more power than then you can get out of it the power essentially comes from the generator. So, logically, the battery ground is mostly needed to the starter, while anything else mostly need a good ground all the way to the generator. They're all linked together one way or another, and the battery ofcourse need a good generator ground for charging so you wouldn't redesign the ground circuits completely to focus on the generator... but it's one of those things you maybe never even thought of.
I hear what you are saying. But I still don’t understand how extra grounds cause this. To me more grounds would actually eliminate it. I don’t understand “ grounded equally” ! Not trying to be an ass, it just doesn’t add up to me! Bones
I too use many grounds. Never a problem, however I don't have a sound system except engine and exhaust. Just my 2 cents worth Ed
Hey @Boneyard51 ! A ground loop would be multiple grounds stacked in one location . Or the same circuit grounded multiple times . If you have a back feed issue or weak ground , the signal or noise can back feed or loop through the redundant ground . when I worked on British junk , there where “ stacked grounds” and you had to make sure you put the grounds back the same way they came off the stud “ 1,2,3,4 ,5,6,7 NOT. 1,4,2,6,3,5 ,7 . If you did not stack the grounds correctly you could end up with a buzzing noise out of a controller or module , or lights not working 100% correctly. not a big deal on our junk . But on more sensitive electronics it becomes an issue, or if you have a “ boom boom” stereo it can pick up interference. You can actually buy “ ground loop isolators” to plug into your amplifiers to eliminate noises . you can google it for a better explanation then I can give you , but this is the gist of it .
The Jalopy Journal
