Starter (solenoid) Location 1974 Cub

[Good Hope Farm]

Hello. I have a general question....If I turn the key and the solenoid under the operators platform makes one single click and does not start, and the battery is new, does that mean the issue is with the solenoid or the actual starter? Or would this be the symptoms of an electrical short somewhere?

[tst]

sounds like a bad connection on the battery cables, ck grounds where the solenoid bolts on also,

[John *.?-!.* cub owner]

Can be looking at different problems, bad battery connection, bad solenoid, or bad starter, or drive teeth of starter jammed in fly wheel. With tractor in neutral, jumper across the 2 large connections of solenoid. If the engine spins over it is the solenoid. If not will need to do some serious trouble shooting.

[Eugene]

Check the voltage drop on you new battery when engaging the solenoid. Could be a bad battery.

[Crimson Tim]

Knowing some history of what lead up to this point would help, and all of the above are possibilities. however, my money is on a connection someplace.
Most probably a ground. Where does your battery ground to? The original battery box location is prone to connection issues. Much better to ground to a transmission bolt.

Conducting a voltage drop test at various points in the system will pinpoint where the bad connection(s) are.
Like John said, jumper across the terminals of the relay. If it suddenly works, the relay is the problem.
Likewise, if you take jumper cables directly from the battery to a known good ground and the starter, and it suddenly works, you know the starter is ok, and there is a connection issue.
If you jump only the positive cable directly to the starter and *not* the negative and it starts, your ground is ok.
Note, you’ll get some pretty good sparks if you jump the starter directly like this.

I’ve been through this recently on a ‘77. It had a bad battery ground to the floor pan. I relocated the ground connection to a transmission bolt and everything was good for a year or so. Then during a damp period this spring where the tractor didn’t get used much, I started having trouble again. I thought the relay went bad, even though it was only a year old. Nope, it’s fine. The battery no longer grounded through the floor pan, but the relay still does. The relay wouldn’t trip because it wouldn’t ground. The corrosion got bad enough to interfere with even the small draw of the triggering the relay. I tried running a jumper ground from the relay to the transmission, which worked, but not well since I didn’t have any real wire connectors available at the time. In the course of using the tractor again, though, actuating the clutch cleaned up that pivot joint enough that it grounds fine through the clutch pivot again. Good enough for the relay. Probably not good enough for the starter.
Some day I’ll fight through the rust to pull off the seat and floor pan to clean that up and repaint, but that’s not going to be any time soon.

[Good Hope Farm]

Thanks to the helpful tips I was able to resolve the issue today. The positive battery terminal connection needed to be replaced and I also relocated the ground connection to a nearby clean, deep bolt rather than the battery box. After that, startup was no problem. Thank you all for the advice, you definitely saved us time and money with this simple fix!