Can I ground my alternator to starter grounding bar

ratface

Member
Tractor is 1949 8N side mount. I have a one wire alternator. Recently discovered alternator was not charging,
( It just needed to be Excited with a jumper from ALT to #1 contact} so did a bunch of reading here and discovered the alternator grounds from the alternator case via the mounting brackets and several here recommended a separate ground wire from Alt. to engine body as an additional backup ground. My closest easiest place to ground would be starter/solenoid copper strap grounding lug. Is this a horrible idea where it will mess with my starting circuit?
 
Tractor is 1949 8N side mount. I have a one wire alternator. Recently discovered alternator was not charging,
( It just needed to be Excited with a jumper from ALT to #1 contact} so did a bunch of reading here and discovered the alternator grounds from the alternator case via the mounting brackets and several here recommended a separate ground wire from Alt. to engine body as an additional backup ground. My closest easiest place to ground would be starter/solenoid copper strap grounding lug. Is this a horrible idea where it will mess with my starting circuit?
1. As long as the alternator mounting bolts are tight IT WILL BE FINE without another ground.

2. The copper strap between the solenoid and starter is NOT a ground, but, rather, is energized to battery voltage during cranking.
 
My closest easiest place to ground would be starter/solenoid copper strap grounding lug. Is this a horrible idea where it will mess with my starting circuit?
Yes, that's a horrible idea. That isn't ground. If your alternator is bolted on it has good ground. If it doesn't charge try revving the engine and see if it self excites without using the jumper wire. Usually the pulley is big and the alternator turns slow at idle and doesn't self excite, you jumping it does that. The fact that you make it charge shows it has ground.
What voltage do you have at the battery, engine off? What voltage do you have at the battery with the engine running?
 
Alternator is charging fine now, I just thought an additional ground wire would be an added layer of protection should the mounting bracket lose ground because of dirt or whatever?

So for learning purposes why is it a horrible idea, why is the starter grounding strap lug not a good grounding point, sounds counterintuitive, does it not touch the starter which grounds on the engine block which would provide an additional ground point for the starter through the alternator body via the mounting brackets to engine ground again.?
 
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Alternator is charging fine now, I just thought an additional ground wire would be an added layer of protection should the mounting bracket lose ground because of dirt or whatever?

So for learning purposes why is it a horrible idea, why is the starter grounding strap lug not a good grounding point, sounds counterintuitive, does it not touch the starter which grounds on the engine block which would provide an additional ground point for the starter through the alternator body via the mounting brackets to engine ground again.?
Are you talking (as two of us thought) about the copper strap between the solenoid and starter, or has the braided "ground" cable from the battery been re-routed to a starter mounting bolt?

A photo would be GREAT, to be sure we are all "on the same page".
 
Tractor is 1949 8N side mount. I have a one wire alternator. Recently discovered alternator was not charging,
( It just needed to be Excited with a jumper from ALT to #1 contact} so did a bunch of reading here and discovered the alternator grounds from the alternator case via the mounting brackets and several here recommended a separate ground wire from Alt. to engine body as an additional backup ground. My closest easiest place to ground would be starter/solenoid copper strap grounding lug. Is this a horrible idea where it will mess with my starting circuit?
HiYa Rat-
B4 you start yanking the ALT off and rewiring, pull your battery and take it to your trusty, local GEN/ALT/STARTER shop and have them test it on their special machine. The battery/power source must sustain a full charge under load to be effective. When left alone with no float charger used when setting idle, battery will begin to lose electrolyte and sulfurization occurs. This is what destroys a battery fast. Your basic garage trickle charger will do little if battery won't hold a charge. My 2nd point is to always have a fan belt tension device attached. Without proper fan belt tension, you will never charge the battery. A loose fan belt will also affect the cooling system. Without proper cooling, this can cause overheating, radiator damage, and water pump damage. Simple as that. Sounds like your wiring is right. Is it 6V or 12V, not that it matters as long as the system is wired correctly for that setup. Are you using a 6V Coil or a 12V Coil? If 6V do you have the external inline 1.6 Resistor in the coil circuit? I advise not be trying to attach wires where they aren't supposed to be, like on the Starter Motor Relay. Do you have the WIRING PICTOGRAMS by JMOR?

Tim Daley (MI)
 

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I am sorry for not being more specific but my charging system is working just fine thanks to this Board. I have a 12 volt system wired per JMORS diagram for one wire alternator/side mount coil. The battery is brand new this year. My tractor sits for months in the winter and it must be causing the alternator to lose magnetism. The simple jumping trick got it going again immediately. While researching the alternator fix I learned that some recommended a separate ground wire for the one wire alternator and just thought is was easy backup insurance should the mounting brackets get all mucked up and lose contact. I bought a grounding strap and the length and size of the eyelets were a perfect fit on the starter grounding lug. Since it's referred to as the starter ground lug/strap it made sense especially if you consider that the starter sometimes loses ground to the mating surface of the block. Thought I was killing two Birds with one grounding strap. As the Board has pointed out it is a bad idea and I will not do it or just ground to the engine block alternatively.

At this point I am convinced it is a bad idea but wanted to understand why it was wrong. From what I have read in searching the forum the Trans push button starter is wired to only energize the starter while the tractor is in neutral so the starter isn't always energized but is it always grounded by being attached to the Block?
 
I am sorry for not being more specific but my charging system is working just fine thanks to this Board. I have a 12 volt system wired per JMORS diagram for one wire alternator/side mount coil. The battery is brand new this year. My tractor sits for months in the winter and it must be causing the alternator to lose magnetism. The simple jumping trick got it going again immediately. While researching the alternator fix I learned that some recommended a separate ground wire for the one wire alternator and just thought is was easy backup insurance should the mounting brackets get all mucked up and lose contact. I bought a grounding strap and the length and size of the eyelets were a perfect fit on the starter grounding lug. Since it's referred to as the starter ground lug/strap it made sense especially if you consider that the starter sometimes loses ground to the mating surface of the block. Thought I was killing two Birds with one grounding strap. As the Board has pointed out it is a bad idea and I will not do it or just ground to the engine block alternatively.

At this point I am convinced it is a bad idea but wanted to understand why it was wrong. From what I have read in searching the forum the Trans push button starter is wired to only energize the starter while the tractor is in neutral so the starter isn't always energized but is it always grounded by being attached to the Block?
This is where a picture of what you are describing might help. We still do not understand what you are calling the "starter grounding lug". To my knowledge those starters have no grounding lug. Is this what you are calling the stud terminal on the starter, because that was the name used for the ground strap you purchased and where it reached to? If so, had you connected that strap from the alternator ground bolt to that stud, you would have created a dead short, sending battery power to ground when you pushed the starter button. The insulated terminal stud on the starter that the battery cable (or flat copper strap from a solenoid) attaches to, is not a grounding lug, it is the point where power is supplied to the starter internals.

The starter is not always energized. The starter internals receive power through that insulated lug to make the starter turn only when the start button is pushed. The starter is always grounded, through its metal body to the chassis where it attaches, when all is clean and in proper working condition. HTH
 
Jim you nailed it, since they call that Brass strap the "grounding strap" I thought it would make a good and easy ground for the Alternator as well and at the same time provide the starter with another path to ground. I appreciate you taking the time to work through my primitive wiring skills, sometimes a fellow can overthink something, thank-you, definitely will not ground there!
 
Jim you nailed it, since they call that Brass strap the "grounding strap" I thought it would make a good and easy ground for the Alternator as well and at the same time provide the starter with another path to ground. I appreciate you taking the time to work through my primitive wiring skills, sometimes a fellow can overthink something, thank-you, definitely will not ground there!
Who is the "they" that call that brass/copper strap between the solenoid and starter stud, in the picture JMOR posted, a grounding strap?
 
an excellent job of working the sword of damocles battery into another thread :D

plenty of us crowbar stuff into threads that has no business being there. but some people see it as both an opportunity and an artform.
"sword od damocles"? That is a swinging battery mount.:D
 
Did you try what I said about checking voltage, and revving the engine to see if the alternator is charging properly and if it starts charging from turning faster?
 
Jim I have read some threads here where the copper strap was referred to as a "Ground strap" or someone has recommended cleaning the, " copper grounding strap". It certainly is an inaccurate description in that sense as it is merely a conductor.

Eman85 to answer your question my battery was testing at 13.6 with alternator not running and somewhere in the mid 14 range running after I excited it by jumper. The battery again is new, which replaced a six year old battery, which failed because it wasn't being charged. My ammeter shows a charge after a slight increase in engine speed now. I suspect my issue comes from letting the tractor sit for months and the alternator losing it's magnetic field. I ran across an article which compared it to making an electromagnet as a kid with wire and a nail, then disconnecting the battery from the nail and that nail will retain some magnetic properties for some time but eventually loses its magnetism. This is my personal assumption of what is happening to my Alternator from sitting all winter, hence why I had to excite my self exciting alternator.
 
Jim I have read some threads here where the copper strap was referred to as a "Ground strap" or someone has recommended cleaning the, " copper grounding strap". It certainly is an inaccurate description in that sense as it is merely a conductor.

If you are having issues getting a good ground through the alternator bracket, there is no reason that you cannot make a jumper to the block. As you have come to realize, this cannot connect to the starter “hot” lead. But any place you can make a good connection to steel should be of help.

Chris from CLE
 

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