WD Welder

[*jdub]

My 1953 Allis Chalmers WD has an identity crisis. It seems to think it's a Lincoln Welder instead of a tractor. It has been sitting for a couple of years and I'm trying to get it running again. I worked on it last spring and when I hooked up the battery, there was lots of sparks and smoke. I got frustrated and walked away, but now I'm back at it. I put new plugs, wires, cap & rotor, points and condenser, and coil on. I removed all the wiring and I'm starting from scratch. I ran a wire from the coil to a switch and hooked it on at the starter lug for power. I checked for continuity through the coil and then attached the positive post of the battery to the starter. When I went to hook up the ground cable, it started to spark to the point that it took a chunk off of the battery post. I removed the coil wire from the system and tried again, only having the starter connected and again with the fireworks. It's got me stumped.

John

 

[old]

Is it still 6 volts or is it 12 vol

My 1953 Allis Chalmers WD has an identity crisis. It seems to think it's a Lincoln Welder instead of a tractor. It has been sitting for a couple of years and I'm trying to get it running again. I worked on it last spring and when I hooked up the battery, there was lots of sparks and smoke. I got frustrated and walked away, but now I'm back at it. I put new plugs, wires, cap & rotor, points and condenser, and coil on. I removed all the wiring and I'm starting from scratch. I ran a wire from the coil to a switch and hooked it on at the starter lug for power. I checked for continuity through the coil and then attached the positive post of the battery to the starter. When I went to hook up the ground cable, it started to spark to the point that it took a chunk off of the battery post. I removed the coil wire from the system and tried again, only having the starter connected and again with the fireworks. It's got me stumped.

John

ts. 6 Volts would be positive ground 12 negative ground

 

[*jdub]

Converted to 12 volts several years ago. Alternator is still on the tractor, but wiring has all been removed.

 

[Fordy20]

Any chance it's a positive ground and you're hooking it up as a negative ground? Don't know about Allis, but my JD G of that era is a positive ground.

 

[old]

Converted to 12 volts several years ago. Alternator or still on the tractor, but wiring has all been removed.

Okay so you have a dead short some place. I'd disconnect the alternator wiring and try it that way

 

[*jdub]

Okay so you have a dead short some place. I'd disconnect the alternator wiring and try it that way

That's already been done

 

[*jdub]

Any chance it's a positive ground and you're hooking it up as a negative ground? Don't know about Allis, but my JD G of that era is a positive ground.

I'm starting from scratch, making it a 12V negative ground. No wiring is left on the tractor at this point, other than the positive battery cable to the starter and negative post to the ground cable.

 

[DaveBN]

If you have an ohm meter test from the case of the starter to the post where you put the battery cable. I suspect it's a dead short. So you'll have a bad starter or possibly a bad switch if the switch is mounted on the starter.
If you don't have an ohm meter then take the starter to a repair shop and have them test it.
Dave

 

[*jdub]

If you have an ohm meter test from the case of the starter to the post where you put the battery cable. I suspect it's a dead short. So you'll have a bad starter or possibly a bad switch if the switch is mounted on the starter.
If you don't have an ohm meter then take the starter to a repair shop and have them test it.
Dave

After the sparks stopped the first time, I cranked it to see if it would fire. The starter spins just fine. Is it still possible that it's shorting out ? What should the ohm meter read between them - zero (continuity) ?

 

[DaveBN]

With the starter switch off you should not have continuity from the starter post to the case.
Dave

 

[*jdub]

With the starter switch off you should not have continuity from the starter post to the case.
Dave

There's no switch between the battery and the starter. It's manually engaged by a rod from the driver's seat. I will check this out when I get home today. Thanks, Dave.

 

[used red MN]

Hello Jd, welcome to YT. I am not an Allis guy but if they use a Delco starter or even any other brand, either the insulation for the stud that the battery cable connects to has shorted to ground. Or the internals of the switch on the starter have come apart and are somehow shorting the starter battery cable terminal to ground. Also as has been mentioned above the majority of 12 volt alternators require a negative ground. Connecting them backwards will damage them.

 

[*jdub]

Hello Jd, welcome to YT. I am not an Allis guy but if they use a Delco starter or even any other brand, either the insulation for the stud that the battery cable connects to has shorted to ground. Or the internals of the switch on the starter have come apart and are somehow shorting the starter battery cable terminal to ground. Also as has been mentioned above the majority of 12 volt alternators require a negative ground. Connecting them backwards will damage them.

I plan to have the alternator checked out at some point. I removed all of the old wiring in an attempt to root out this issue, so the alternator has been isolated. Once I get this under control, I can start putting it back together.

 

[Jim.ME]

I plan to have the alternator checked out at some point. I removed all of the old wiring in an attempt to root out this issue, so the alternator has been isolated. Once I get this under control, I can start putting it back together.

If all the wiring is unhooked except the battery cables, used red pretty much has the answer. the positive/hot battery cable has grounded somewhere along the way, the manual switch the rod operates to engage the starter or something has gone to ground in the starter, like the insulation around the contact stud under the switch cover.

 

[*jdub]

If all the wiring is unhooked except the battery cables, used red pretty much has the answer. the positive/hot battery cable has grounded somewhere along the way, the manual switch the rod operates to engage the starter or something has gone to ground in the starter, like the insulation around the contact stud under the switch cover.

Thanks, Jim. I'm hoping to dig into it tonight and see if I can figure out where the issue is.

 

[*jdub]

I will do some digging tonight and hopefully provide an update tomorrow

 

[Janicholson]

Ohm meters cannot check starter motors (at their input terminals on their case). They have internal resistance less than one ohm. An expensive lab certified device would, but common hand held meters are not sensitive enough. continuity through the saddle switch on the starter motor will work well. Put the meter in Ohms position (or continuity position) then touch the probes together. the reading should be at or near zero. then touch the starter on a bare metal spot with one lead, and the other on the saddle switch input stud. It should not read anything (or not make the continuity tone). if it does, that switch is shorted to the case internally. Jim