Converting a WD to 12 volt

 

Kicking around the idea of converting the WD to 12 volts. I know lots of people have, but what exactly does it all take?

 

 1. Its a magneto ignition, so that shouldn't require anything at all, correct?

 

 2. The 6 volt starter is just about kaput. Do you just have it rebuilt with 12 volt windings, or is there more to it?

 

 3. I have no problem making brackets to mount an alternator. I thought about getting one of those mini ones that are about 35 amp. I know I've read on here about having to rev up the engine to get certain ones excited. I thought a guy could put a smaller pulley on, or turn the existing pulley down smaller to make it spin faster. Always good to have a machinist friend... 

 

 4. In a pinch, is it O.K. to jump start a 6 volt system with a 12 volt battery? I know it works, but can you wreck something? I tried it once, I hooked up the jumper cables, pulled the starter rod, and unhooked them immediately. Boy, I've never heard that tractor spin over that fast. I'm not sure if the impulse was even working! The engine in my pickup sure bogged down when I hooked up the jumper cables, though.

 

 

I'd like to keep the tractor original, but it sure would be nice to run LED's, an electric water pump, sprayer, maybe a winch, stuff like that.

 

 

Edited by littlemarv - 04 Mar 2018 at 7:16am

1)  Nothing required as far as changing the ignition circuit is concerned.    

Edited by DougS - 04 Mar 2018 at 7:45am

Make sure to check the field coils to see if they are shorting to the case. I have wrapped a piece of black tape to stop that. If you have a starter shop where you live you can take it there to see where anything is shorting out. When putting the starter back in don't over tighten the set screw as you can distort the case and bind things up. In fact it might be a good idea to check it and see if that is what is happening.

So, can I get the starter rebuilt and then just hook it up to either 6 or 12 volts?

Oh yeah, forgot to mention a couple weeks ago, the steel band came off the back of the starter, revealing a layer of duct tape. That just can't be good.

I've never thought about it. Can you buy a new starter? Just in case my case is shot or something.

littlemarv wrote: So, can I get the starter rebuilt and then just hook it up to either 6 or 12 volts? Oh yeah, forgot to mention a couple weeks ago, the steel band came off the back of the starter, revealing a layer of duct tape. That just can't be good. I've never thought about it. Can you buy a new starter? Just in case my case is shot or something.

The only thing I understand about the starter using 12v is don't grind on it very long at a time if it won't start. I guess starter really doesn't care if 6 or 12v. Check out Duey's page    http://dueyschutter.freeservers.com/

We offer a complete 12V conversion kit for the WD/WD45 if interested. Visit our website. There's plenty of info on conversions, what to do, what not to do etc. Plenty of pics also to look at. Pics of the wiring systems also.  Be glad to help ya out anytime.  Forgot to mention, if your Starter is about done, I can change it over to 12V's the correct way. Its always better to change the Starter to 12 if your going to convert the system to 12. Appling 12V's to a 6V Starter motor makes the Starter violent. This could lead to broken nose cones, damaged ring gears etc.  HTH

Edited by Steve in NJ - 04 Mar 2018 at 10:59am

When it was absolutely necessary to jump a 6 volt tractor with a 12 volt, I have jumped directly to the starter....a bit of fire when you make the connection but it bypasses all the 6 volt stuff. With battery ignition, your 6 volt battery has to have enuf life to provide fire to the points.

Stick with a 3 wire alternator, it's not that hard to do and the exciter circuit will lower the RPM to get it charging. On my WD I put a charging light on the dash to serve as the exciter amp draw, once I rev the engine a little bit the light goes out and the volt meter jumps up to around 14v and stays there even if I throttle back, charges good.

Kind of glad I started this thread. You guys are reminding me of everything I'm neglecting! Come to think of it, I have never put plugs and wires on it, or set the valves. I guess it's time to perform all the maintenance I have been "too busy" to get done. It starts better in the summer, but now that I have been using it in the winter, problems have been creeping up.

 

When I go up to dads, I'm always in a hurry. Gotta run up there, usually with at least one kid, try and get something done, then scramble back to town for the next sports or family or school event.  And heaven knows, if you are in a hurry, nothing goes right so everything takes longer anyways.  The WD has always been the workhorse.  I've always just jumped on it, did what I could, and left.

Anyways, here's the starter and cables.

 

 

 

 

 

And here is a video of how it starts....eventually.

 

https://www.youtube.com/watch?v=LEs77eFsmPk

 

Keep in mind, it usually starts a little better than this, I just crank it and pull the choke rod out, as soon as it pops once, shove the choke back in and off it goes.  But I didn't have enough hands while filming.

 

So, since it will be mud season before you know it, and warming up a bit, might be the perfect time to rebuild the starter, new cables, plugs and wires, and valve adjustment, before we start field work in the food plot.

 

What is the recommended size battery cable for 6 volt?

Edited by littlemarv - 04 Mar 2018 at 8:57pm

Found some other posts, looks like 00 gauge is the way to go.

Actually turned over quicker than I expected. Much faster than dads CA even with a new battery. His starter stops after a revolution or so of the engine. Two quick pulls of the starter rod and then it usually starts. May need to look into larger battery cables and a starter rebuild also. I dont want to convert his to 12v if I can resolve the issue.
Good post

Basically it boils down to with a 6V system you hope it'll start,with 12V you make it start.
12V is a lot easier on the starter because the engine will almost instantly fire up
once you hit the starter.Also 6V batteries don't hold up well compared to12V I've used.
We struggled with our WD45 for years with a 6V system then finally changed over to
12V should have done it years before we did.Was very nice to go out on a 10 degree morning and hear the motor spin over and fire right up.
When it comes to a tractor I'm using to work with I want what works best not some antique system that was state of the art 50 years ago.You still use the same phone(if you even had one) that you used 50 years ago?

If originality is very important, stick with 6v, replace the cables, clean all the connection points.  If you want faster cranking, lower battery maintenance, a greater choice of batteries, the ability to jump-start other machines (and have them jump-start you), would like to add great lighting or other electronics, swap the battery to 12v negative ground, put on an alternator, and replace the bulbs in all the lamps.  I've converted all mine, and a dozen of others', for those reasons... with absolutely no complaints of any kind.

One thing that nobody has noted-  the worst thing you can do to a starter motor, cables, solenoid, and battery, is underpower it.  When you stall or drag a starter motor, the windings carry substantially more current, and the stall and drag is irrelevant of reason- poor bearings, worn brushes, or insufficient current and voltage supply from the system.   When you provide ample voltage and current to spin the starter motor, it's draw is lower, because the higher armature speed means faster commutation, and the reactance in commutation is substantially higher.

The starter in my Hercules 338ci JXLD inline six is a 24v DELCO starter.  I'm cranking it with a 12v 4D truck battery, and it rolls it over just as well at 12v as it does it's original 24v... it just draws three times as much current.  When I took it to my local shop for a rebuild, I asked them what it'd take to swap the windings for 12v operation, he looked it up, and said same starter uses all same componentry, and same wiring... no difference between 12v and 24v for that unit... just a different solenoid winding, and a different reading on the meter under load testing.

Now, I took a listen to your WD start, and what's happening, is that when your engine crosses TDC and SLIGHTLY fires, the starter is unable to 'stay with' the ring gear as it speeds up.  By the sound of your starter bendix, I'd say you'd benefit from a starter rebuild.  The kicking out is not only annoying, it's hard on the ring gear and starter bendix.

The ground strap is a bit long, but that's probably not having as much impact as the ground connection path from the cover bolt to the starter housing.  On these, the starter nose is simply slid into the torque tube casting, and a binding bolt clamps down on the starter nose shell.  When you rebuild the starter, cleaning the casting, nose, and that bolt point and threads WILL help.  I don't understand why AC didn't spec a grounding lug on the side of the starter shell, but they didn't.

Your magneto impulser sounds really sharp and loud... perhaps it's just your camera and the inside of he building, but all my magnetos aren't that bright and metallic-sounding...  almost sounds like the impulser's internals are hammering against the housing a bit.

If you really, really, really want a good-starting tractor, hand-crank it... and then get the carbeuration an magneto set up so that it'll hand start easy.  After that, it doesn't matter WHAT condition the battery, cables, and starter are in, it'll still start easy...


Edited by DaveKamp - 05 Mar 2018 at 9:50am