Starter Relay on 850 Driving Me NUTS!!!

2nd posting on this issue. After Resto on my 1957 850 with 12 V conversion also, my starter would not stop running when button was pressed until I removed battery cables. Forum response was to change my 6V starter relay for a 12 V relay, specifically a NAPA 12 V ST542. I did that this week, and now starter will not start at all. I don't have a multimeter, but I do have a 12 V light continuity tester. I have removed trans lid and double checked starter button as well (i.e. neutral lock). Has a new fully charged 12 V Gel battery. There are no fuses or resisters installed anywhere in the wiring for the starter circuit. I checked All grounds and grounds are all fine, i.e. frame, solenoid/relay metal frame and 2 mounting bolts, trans lid, starter motor, etc. When button is depressed, light goes on when tested to relay battery terminal. Also light comes on when tested from relay battery terminal to both of the smaller bottom terminals. And is on all the time when connected to starter terminal (because starter motor is grounded to frame). Wire test from relay starter terminal to switch and other small terminals never lights up. No continuity between smaller two terminals at any time (switch depressed or not). My wiring matches all the relevant archive diagrams for 12 V conversions. So, I know starter works, I know switch works. I have a brand new relay/solenoid. Can my relay be faulty right out of the box? If I get a multimeter, how do I test either on or off the tractor if the relay is good or bad? Any thoughts, experiences, etc. may help me avoid a complete mental breakdown. I'm trying here guys, but this one is just killing me. Thanks, Larry.
 
(quoted from post at 21:10:15 10/08/19) 2nd posting on this issue. After Resto on my 1957 850 with 12 V conversion also, my starter would not stop running when button was pressed until I removed battery cables. Forum response was to change my 6V starter relay for a 12 V relay, specifically a NAPA 12 V ST542. I did that this week, and now starter will not start at all. I don't have a multimeter, but I do have a 12 V light continuity tester. I have removed trans lid and double checked starter button as well (i.e. neutral lock). Has a new fully charged 12 V Gel battery. There are no fuses or resisters installed anywhere in the wiring for the starter circuit. I checked All grounds and grounds are all fine, i.e. frame, solenoid/relay metal frame and 2 mounting bolts, trans lid, starter motor, etc. When button is depressed, light goes on when tested to relay battery terminal. Also light comes on when tested from relay battery terminal to both of the smaller bottom terminals. And is on all the time when connected to starter terminal (because starter motor is grounded to frame). Wire test from relay starter terminal to switch and other small terminals never lights up. No continuity between smaller two terminals at any time (switch depressed or not). My wiring matches all the relevant archive diagrams for 12 V conversions. So, I know starter works, I know switch works. I have a brand new relay/solenoid. Can my relay be faulty right out of the box? If I get a multimeter, how do I test either on or off the tractor if the relay is good or bad? Any thoughts, experiences, etc. may help me avoid a complete mental breakdown. I'm trying here guys, but this one is just killing me. Thanks, Larry.
ll that is completely meaninglessness without knowing where and how each end of your light was connected.
 
(quoted from post at 19:36:31 10/08/19)
(quoted from post at 21:10:15 10/08/19) 2nd posting on this issue. After Resto on my 1957 850 with 12 V conversion also, my starter would not stop running when button was pressed until I removed battery cables. Forum response was to change my 6V starter relay for a 12 V relay, specifically a NAPA 12 V ST542. I did that this week, and now starter will not start at all. I don't have a multimeter, but I do have a 12 V light continuity tester. I have removed trans lid and double checked starter button as well (i.e. neutral lock). Has a new fully charged 12 V Gel battery. There are no fuses or resisters installed anywhere in the wiring for the starter circuit. I checked All grounds and grounds are all fine, i.e. frame, solenoid/relay metal frame and 2 mounting bolts, trans lid, starter motor, etc. When button is depressed, light goes on when tested to relay battery terminal. Also light comes on when tested from relay battery terminal to both of the smaller bottom terminals. And is on all the time when connected to starter terminal (because starter motor is grounded to frame). Wire test from relay starter terminal to switch and other small terminals never lights up. No continuity between smaller two terminals at any time (switch depressed or not). My wiring matches all the relevant archive diagrams for 12 V conversions. So, I know starter works, I know switch works. I have a brand new relay/solenoid. Can my relay be faulty right out of the box? If I get a multimeter, how do I test either on or off the tractor if the relay is good or bad? Any thoughts, experiences, etc. may help me avoid a complete mental breakdown. I'm trying here guys, but this one is just killing me. Thanks, Larry.
ll that is completely meaninglessness without knowing where and how each end of your light was connected.

JMOR, I could be wrong but it appears to me that Larry is just looking for guidance on where to connect his light.
 
There is an excellent article here on YT that gives a detailed step by step instruction for doing a 12V conversion. It also lists the following test procedure:

"With a small DC test light, hook the light ground clip to the "-" side of the battery. Turn the switch on and observe the voltmeter mounted in the dash - It should rise to 12 volts (or close to it).

a. Touch the battery side of the solenoid with the test light - the light should come on.
b. Touch the "I" post on the front of the solenoid with the test light - the light should come on.
c. Touch the "S" post on the front of the solenoid with the test light - the light should come on.
d. Touch the "+" post on the coil with the test light - the light should come on.
2. If all the above check out, hit the starter button. It should spin over MUCH faster than with the 6 volt system, and will probably crank almost immediately. (Be aware that now you are sending 12 volts to a starter designed for 6 volts. The starter could be damaged by excessive cranking, so if she doesn?t start pretty quickly, let the starter rest between attempts. I personally won?t let the starter run over about 5 to 7 seconds at a pop.) The voltmeter should read about 13.5 to 14.5 volts with the engine running. If it stays at 12, rev up the engine. Mine took this to begin charging. Don't forget to put the air cleaner back on."

The complete article found here:
12v conversion
 
(quoted from post at 21:10:15 10/08/19) 2nd posting on this issue. After Resto on my 1957 850 with 12 V conversion also, my starter would not stop running when button was pressed until I removed battery cables. Forum response was to change my 6V starter relay for a 12 V relay, specifically a NAPA 12 V ST542. I did that this week, and now starter will not start at all. I don't have a multimeter, but I do have a 12 V light continuity tester. I have removed trans lid and double checked starter button as well (i.e. neutral lock). Has a new fully charged 12 V Gel battery. There are no fuses or resisters installed anywhere in the wiring for the starter circuit. I checked All grounds and grounds are all fine, i.e. frame, solenoid/relay metal frame and 2 mounting bolts, trans lid, starter motor, etc. When button is depressed, light goes on when tested to relay battery terminal. Also light comes on when tested from relay battery terminal to both of the smaller bottom terminals. And is on all the time when connected to starter terminal (because starter motor is grounded to frame). Wire test from relay starter terminal to switch and other small terminals never lights up. No continuity between smaller two terminals at any time (switch depressed or not). My wiring matches all the relevant archive diagrams for 12 V conversions. So, I know starter works, I know switch works. I have a brand new relay/solenoid. Can my relay be faulty right out of the box? If I get a multimeter, how do I test either on or off the tractor if the relay is good or bad? Any thoughts, experiences, etc. may help me avoid a complete mental breakdown. I'm trying here guys, but this one is just killing me. Thanks, Larry.
ou say, "No continuity between smaller two terminals at anytime.." I have no idea how you determined that, but if correct (& I am suspicious), then as you can clearly see in the attached schematic of ST542, that there should be continuity via the coil of wire.
YyB05a2.jpg
 
OK, I learned a lot from a half hour tutorial I received on a phone call tonight (Wed) with a friend. I learned how little I know about electricity. I did NOT check continuity, only which terminals were getting power using my test light, which by the way, I used backwards. I learned what a solenoid / relay looks like inside and exactly how it works, (how power to the coil draws down the heavy copper bar to connect the two large terminals) and I learned how to use just my test light to get some additional info. I am going to use the very useful information you guys gave me, coupled with what I learned tonight, and test all pathways and terminal correctly tomorrow, and hopefully I will get it all sorted out. I will get a continuity tester (multimenter) as well. Thanks again guys, very much appreciated all your help especially the diagrams from JMOR I will keep you posted on exactly how I resolved the problem. Best to all, Larry.
 
GOT IT WORKING!!! Here is the story. Firstly, like so many, I just wanted to bolt the relay on, attach the wiring, and get the tractor started. Wrong approach. What I should have done right from the start is the understand how a relay actually physically works. Once I did, it was easy to find a solution. Also, when I switched from a single (S) post 6 V relay to a double post 12 V ( S & I ) relay, I got really confused because I did not know what these terminals attached to inside the unit. Once I learned about the coil inside, the proverbial light went on above my head. Also, although I completely wired my own home, new circuit boxes, all new wiring, switches outlets, etc. etc., ( I know all about line & load and grounds, etc.) I never heard of a "ground switch" which is what my tractor switch is. How can a switch only have a single wire? This also led to my using my 12V light tester the wrong way because I just could not figure out how my starter switch was getting any power (back it it is a ground switch you idiot.) So now I know. JMORs diagram really helped, and I am truly grateful. My 1925 Fordson was a lot easier, but not much of a challenge. Thanks again to ALL, Larry.
 
(quoted from post at 17:18:07 10/10/19) GOT IT WORKING!!! Here is the story. Firstly, like so many, I just wanted to bolt the relay on, attach the wiring, and get the tractor started. Wrong approach. What I should have done right from the start is the understand how a relay actually physically works. Once I did, it was easy to find a solution. Also, when I switched from a single (S) post 6 V relay to a double post 12 V ( S & I ) relay, I got really confused because I did not know what these terminals attached to inside the unit. Once I learned about the coil inside, the proverbial light went on above my head. Also, although I completely wired my own home, new circuit boxes, all new wiring, switches outlets, etc. etc., ( I know all about line & load and grounds, etc.) I never heard of a "ground switch" which is what my tractor switch is. How can a switch only have a single wire? This also led to my using my 12V light tester the wrong way because I just could not figure out how my starter switch was getting any power (back it it is a ground switch you idiot.) So now I know. JMORs diagram really helped, and I am truly grateful. My 1925 Fordson was a lot easier, but not much of a challenge. Thanks again to ALL, Larry.
appy for you & you are welcome.
 
(quoted from post at 07:28:15 10/09/19) Forgot to mention for test, key must be switched on.

Actually you didn't. It was there in the first paragraph before the numbered list:

"With a small DC test light, hook the light ground clip to the "-" side of the battery. [b:07e39fefe6]Turn the switch on[/b:07e39fefe6] and observe the voltmeter mounted in the dash - It should rise to 12 volts (or close to it).
 

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