positive ground 6 volt

[Deleted User]

My 37 Terraplane ground strap is from batt. to engine cylinder head stud. The book shows it thru the panel to a inner fender ground was this a bad idea? I noticed most cars have it to the cyl. head like mine. Or is this just a better ground?

[Deleted User]

Chuck G wrote:

My 37 Terraplane ground strap is from batt. to engine cylinder head stud. The book shows it thru the panel to a inner fender ground was this a bad idea? I noticed most cars have it to the cyl. head like mine. Or is this just a better ground?

The ground for any automotive electrical system must be the least resistant means of connection all the ground potential elements. If the engine is grounded to the body and the frame and the remaining electrical components are electrically connected to the either the body, frame or engine. The circuits should operate at peak efficiency.



All of this rhetoric is moot if the connection points are not kept clean and tight. The engine head is usually a good ground point.

Jon B

There should be two ground strap connections. Originally, the ground strap may indeed have gone from the battery terminal, but there should also be a strap from the body to some point on the engine or transmission. In my car it goes from the cross member under the transmission, to the bellhousing or engine mounting plate, as I recall.



Remember that the battery CABLE must be the thicker, 6-volt type. Not the modern, thinner 12 volt type.

[Deleted User]

My 55 Hash is negative ground six volt though everything says it should be positive ground. Since it is all DC current I'm not sure that it matters, the starter turns the correct direction and the generator is charging. Is there a reason I'm missing that the battery should have a positive ground?



Harry

Geoff

Yes, the points in the voltage regulator are of a dis-similar metal, and continued use with negative ground will eventually lead to faliure of the voltage coil points. Change it over. All you need to do is trun the battery around, temporarily jumper the "F" terminal to ground, and the B and A terminals need to be connected together for a very short time, to re-polarise the generator.

Geoff.

[Deleted User]

Okay Geoff, thanks for letting me know,but won't changing polarity cause the starter to turn in the opposite direction? I'm not good at electricity but I know when I was a kid if I wanted a motor to turn the opposite direction all I had to do was switch poles from the power source. I thought this car should be positive ground but was told by an old time mechanic that about 55 is when they were switch all the cars to twelve volt, negative ground and my car could have been an early swap while still 6 volts, didn't sound quite right but I'm not an expert.



Harry

[Deleted User]

Thanks for all the great comments, I Have the correct 6 volt cables and my chassis is grounded as you described Jon i just thought i might run the ground strap thru the original grommeted hole might look better than to the cyl. head wrer it is at now.

Geoff

Harry Hill wrote:

Okay Geoff, thanks for letting me know,but won't changing polarity cause the starter to turn in the opposite direction? I'm not good at electricity but I know when I was a kid if I wanted a motor to turn the opposite direction all I had to do was switch poles from the power source. I thought this car should be positive ground but was told by an old time mechanic that about 55 is when they were switch all the cars to twelve volt, negative ground and my car could have been an early swap while still 6 volts, didn't sound quite right but I'm not an expert.



Harry

The only way you can make the starter turn backwards is to reverse the field connections. These are series motors, so it doesn't matter which way round the battery voltage is connected. You will also need to check the coil polarity when you reverse the battery.

Geoff.