Alliis Chalmers CA Wiring

Hi,

I am trying to bring a CA back to life. The engine seized so I ended up taking the heads off and honing the cylinder walls. I then replaced all of the gaskets since everything was basically tore down. I sealed everything back up and am having issues with cranking.

The starter is new, the positive is grounded to the frame and the negative is connected to the battery. 1 gauge wires. The battery is new and the plugs are new/gapped correctly.

Before I did that, I used the wiring diagrams posted here and re-wired it back to a positive ground. When I crank the engine, she cranks fine with no spark plugs. When I put plugs in, the engine cranks slowly and intermittently.

The electrical had been re-wired already. I intend to replace all of the wiring as the wires seem like they have seen better days and are not very bendable. It leads me to believe maybe a wire or two are corroded inside and can’t provide enough current for the system to crank.

Can anyone provide the wiring specs? Not sure which gauge(s) of wiring to buy. I’m not looking for a harness as they are expensive.

I checked all of the wires for current and connected them to the correct places on the generator, coil and cutout. What else can I check? The ammeter seems ok, but the light switch is stuck.

I also don’t know the condition of the generator and cutout, but it was a running tractor when I bought it a couple of years ago.

It sat, the engine seized, now the thing won’t crank, lesson learned. Suggestions?


Edited by pudi211 - 30 Dec 2024 at 10:06am

for a test, you can install a 12 volt battery and crank the engine over... Just dont turn on the lights ... long term not a good idea with a 6 volt coil / distributor ... you could take  the wire off amp meter to kill Everything except the starter / battery connection.

So a short in the system won’t cause slow cranking? Yes, it’s a 6v system with a new battery. Starter and switch are new. Terminals are new and clean, ground is freshly stripped and grounded now to the frame. It was cranking fine on 1ga before I parked it. Thinking about it, I guess the battery and ground cable are the only ones that control cranking so it makes sense. I wonder if the battery is not strong enough even though it’s new.

Edited by pudi211 - 30 Dec 2024 at 11:11am

I’ll give that a try too. No lights on the tractor currently.

Ok, I disconnected all wires except for the battery/ground cables. Same slow intermittent lope.  Not a steady crank.  I purchased the battery over the weekend, and I am charging it now.  Starter is new and the battery is new.  I also tried two different grounding points. I installed the old starter, which probably wasn't bad to begin with, and the result is the same as with the new one.  The old starter actually cranked better than the new one.  Thinking it just could be a crappy battery.    

Cables do make a big difference..  #1  is .065 square inches cross section.  00 has a  .1054 square inch cross section or 60% larger. ........... but im still not convinced thats your problem.. but would make a difference in current carry.

Edited by steve(ill) - 30 Dec 2024 at 4:51pm

lights, ignition, distributor, coil.. etc... can all be 18 gauge.... Might use 16 guage to make it more BEFFY and rigid... Too much bigger and you cant get the wires into the switch box..

Edited by steve(ill) - 30 Dec 2024 at 6:00pm

The battery may be new but does it have high enough cranking amps? Our CA rolled over slowly on 6V and required a really good battery but usually fired up within a rotation or 2. Eventually we changed it over to 12V. I’m like Alvin, I use 2/0 welding cable, also good quality crimp connectors. Make sure you use + and - size connectors for the battery, they are different sizes. Positive is a larger connector and most parts stores only sell the larger size. Doesn’t work well on negative post of the battery as it can’t provide the clamping force because of its large size. Our local battery supply store crimps the connectors for you if you purchase the cable and connectors from them. I have my own crimp tool which will crimp 12 different size connectors. It’s a $600 tool but was tired of getting crap cables from auto parts stores. It makes a huge difference in how a starter will spin an engine over. Money well spent and have crimped a lot of cables with it over the years for myself and my friends.

Thanks Steve.  I appreciate the good advice and hopefully others will benefit from those specs.

Appreciate it.  I'll be replacing all of the wiring and ring terminals.  I put a Deka battery on it yesterday and the cranking was slightly better.  

Edited by Les Kerf - 31 Dec 2024 at 10:20am

I have a B with a Sickle and another with a Belly mower.. They share the same 12v battery . I move it back and forth 4-5 times during the summer.. I have notice a  BLACK corrosion on the inside surface of the battery clamp terminals once or twice a year.. This is not the green/ white CRUD that seems to GROW on some terminals.. This is a very think BLACK coating that looks almost like it was spray painted on ??? ..... I use a sandpaper on a dowel to clean both clamps when i see it.... Few years ago one tractor would not start and i fought it a long time till i figured out the clamp was CLEAN to the eye, but had that black coating... Make sure everything is SHINNY SILVER..