starter ground wire

[Gary Blakeslee]

I am about to rebuild the starter for a 1947 Cadillac and I remember there was talk about installing a ground wire on the starter motor for easier starting.  Would someone have the directions for this and is it a good idea?   Gary B.

[The Tassie Devil(le)]

It is always a good idea to have good grounds.

The Ground Wire on my '72 Eldo goes from one of the mounting bolts directly to the frame, and there is also another ground from the Battery to the Engine Block, and the frame, and body.

Bruce.

[Jay Friedman]

Email me at jaysfriedman@yahoo.com and I'll send you by reply email an article on an improved way to ground your starter.

[Glen]

One of the causes of this problems is too much paint when rebuilding these starters.  Many people do not understand the brushes for the ground connection make their connection through the end frame, then the center frame (case) of the motor, then through the clutch housing to the block.  See the image below.  The red line indicates the path I am trying to describe.  The places where these parts contact each other must be clean of pant and rust.   
The through bolts will also provide a path to ground but the cross section of those bolts are not large enough to provide the necessary amps for the starter, especially when the engine is hot. 

[Bill Ingler #7799]

Gary:  In addition to grounds for the starter, make sure you have grounds from the engine block to the firewall as shown in picture below as well as a left ground strap from left  engine mount to frame as also shown in picture. On a 47, this grounding strap is also on the right engine mount as well.  Bill

[Scot Minesinger]

You really cannot have too many grounds, but too few is no good.  The grounds on my 1970 Cadillac are similar to Bruce's 1972 Eldorado - bullet proof.

[z3skybolt]

1940 LaSalle,

I have the starter ground and one engine to frame ground, cable direct from the battery to the starter. None from the engine to firewall. Maybe I should have. But my LaSalle turns over quickly and starts easily. 6 volt system. Two 6 volt Optima batteries wired together for 1,600 amp of cranking longevity, which is rarely needed but nice on a hot engine day.

bob

[Mike Simmons 938]

Our late, great electrical guru, Doug  Houston,  noted in Forum that the ideal place to locate the ground strap on the starter was at the end frame in the back, where the brush was also grounded. He used a late 40s Olds starter as an example, since they had a stud that served that purpose.  He thought it worthwhile for anyone upgrading his starting system to add such a bolt or stud.
So far as I know, only Olds used such an end frame. It looks like all the other Delco starter end frames up through the 50s, so I GUESS it might interchange.

[TJ Hopland]

I never thought about paint being an issue but that makes perfect sense.   Most starters do have those through bolts so that would be a good place to clean up and maybe add a star washer or connect a cable there as apparently recommended by Doug.    If you are just going with the cleaning method then you would also have to make sure the surface to the bock and block is also clean.

My industry didn't used to have grounding issues till the EPA cracked down on crappy painting and more or less forced everyone to go powder coat.   That was great for looks and durability of the finish but turned out to not be a good thing for equipment grounds.  Before the mounting screws would chip the paint or the paint would just get chipped during assembly and it made contact.   Powder coat turned out to be a durable insulator.  I bet something similar happens with many restorations.  Even if you use the same paint as the factory did hopefully the restorer is careful during assembly,  maybe the factory guys were required to be rough with certain parts just to make sure they made good contact?

[Jay Friedman]

Our late, great electrical guru, Doug  Houston,  noted in Forum that the ideal place to locate the ground strap on the starter was at the end frame in the back, where the brush was also grounded. He used a late 40s Olds starter as an example, since they had a stud that served that purpose.  He thought it worthwhile for anyone upgrading his starting system to add such a bolt or stud.
So far as I know, only Olds used such an end frame. It looks like all the other Delco starter end frames up through the 50s, so I GUESS it might interchange.

Email me at jaysfriedman@yahoo.com and I'll send you by reply email an article on an improved way to ground your starter.

Art Garder's and my article on grounding the starter describes the Doug Houston/Oldsmobile method.