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Hey all,
I just have a quick ground strap problem... My friend was helping me get the car going the other day, and he pointed out that I don't have an engine to frame ground. My old motor didn't have one either, but I never experienced any problems, electrically or otherwise related... So what is the best way to hook up the ground strap? First thought was starter bolt, but the eyelets on my cable aren't that big (holes aren't big, but lots of contact area)... Perhaps I could drill out the eyes on the cable?

i know my V8 has the battery to block ground....and it has an engine to firewall ground strap as well.

I noticed on my '52, that there was no ground strap either. I ended up making one out of 8 gauge wire. It goes from the throttle linkage bracket on the head, to the firewall. There wasn't any problem without one, I just added it for insurance.

-Garrett

Interesting.... Maybe the 6v systems don't use one from factory? The only engine ground I can see in any wiring diagrams is engine to batt. Like I said, all electrical works fine, and the body and frame ARE definitely grounded.... Maybe there is enough things bikers to the frame and firewall (engine mounts, throttle linkage) that it creates It's own ground?? Either way, it runs and operates fine....

Maybe there is enough things bikers to the frame and firewall (engine mounts, throttle linkage) that it creates It's own ground??

I think that has a lot to do with it. Not nearly as many rubber cushions back then as on more modern cars.

One of the posters mentioned some cars having a strap in the transmission area effectively between engine and frame. I don't remember one but honestly, never paid much attention. There is a factory wire ground between body and engine -- granted, not much of one and certainly not direct.

If you will look carefully at the diagram, there is a ground from the generator case -- bolted to engine -- to the left front fender mounting screw for the headlight terminal strip. That ground branches to the other fender to that headlight strip mount and also to the regulator case ground which screws into firewall so effectively, to the body. It's a fairly small wire, but for the few things normally on those cars, probably adequate with the other metal contacts.

The battery is grounded to the engine; if there isn't a separate engine to body strap (as in the V8s), there is often a generator (engine) to body ground. And the body is grounded to the chassis, if no where else, thru the parking brake cable. I've never known the lack of a discrete engine or trans ground strap to the frame to be a problem, but I often see one on the rear transmission mount, just from one side of the mount, around the rubber, to the other side. Might help, can't hurt.

Makes sense... The new battery cable I installed had a body ground terminal so I attached it to the bolt that joins the fender to the radiator core support.

The motor mount design has a lot to do with it. While the engine portion of it sits on a rubber mount, it is not a floating/isolated mount. The central studs are secured to the frame on the bottom, and the nuts contact the engine side of the mount support. So the mounting studs are acting as a constant/direct ground path from the engine directly to the frame. So basically thats four ground points right there.

I believe there is also a ground wire between the generator and the headlight junction block on the fender.

The new battery cable I installed had a body ground terminal so I attached it to the bolt that joins the fender to the radiator core support.

Sounds as if you have a modern cable. If your car is still 6v, one thing to be aware of is 6v systems need a heavy gauge cable. The typical 12v or aftermarket cables are sometimes too small. If you have issues with slow cranking, hard starting because of a voltage drop between battery and coil and resulting weak spark, the cables would be a place to start looking.

No kidding about the small cables being bad!! The old cables were just regular gauge cables that are on the shelf at Napa... It would hardly crank, and the negative cable would get SMOKIN hot. I replaced them with large gauge cables for diesel trucks and not a problem anymore. Cranks over like It's running on 12v!