Ground Issues?

[Jon@HannenFamilyFarm]

1 through 3 are OK. 12.78v means really good battery. 2) is OK since starter isn't cranking (should be roughly 10 to 11 volts while cranking.
"4) now meter positive + lead on battery positive +. Negative lead on starter terminal.
Should be zero volts off & cranking. off 0, ignition in on position 3.49, crank 12.43"
Your battery + positive cable goes to solenoid big terminal, other solenoid big terminal goes to starter. When cranking the solenoid small terminal gets power which engages solenoid so starter gets power.
If you use a jumper cable battery + positive to solenoid big terminal and it cranks normally...you need to replace battery to solenoid cable since you just bypassed it.
If you jumper battery positive to other side of solenoid which goes to starter it should crank. (Careful...it will spark...lots of current there, but it's just a quick test). If it doesn't crank, try at starter itself. If it does crank, replace this cable solenoid to starter since you just bypassed it.
Step 4) getting voltage from battery positive to solenoid & starter proves you have a bad cable or solenoid. NOW...meter negative lead on ground you SHOULD measure 12 volts battery side of solenoid and small terminal and at starter when cranking.

Fuddy1952, thank you very much for your time and help. I greatly appreciate it. I will give it a go in the morning.

 

[jigs_n_fixtures]

I had a car which would do something similar. Except it was intermittent.

Everything would work fine and then the starter would quit working. Pull it out take it to the parts store, and have them check it and everything would work fine. Put it back in, and it would work fine for a few weeks and then quit working. Tested and replaced ignition, starter relay, Added, a braided copper ground direct from the frame to one of the bolts holding the starter, and one from the battery negative directly to the same frame rail.

Kept happening. Finally bought a new starter, and put it in. Decided to tear open the old one before I took it back for the core charge. There was one wire, loose on one end, which I could see had been arcing. If it was lined up right, everything worked fine. Hit a bump, it moved and lost contact. The act of pulling the starter out to check it on the bench had been enough to get it working and testing good.

 

[jaxs]

Because of those hammer marks,I'm going in a different direction and hopfully you don't find it difficult. If the latest electrical tests don't turn up anything,look at this. When the starter was off,you noticed a gear and spring apparatus (Bendix). The gear might be stuck engaged with flywheel ring gear. If there's an inspection plate that alow's viewing, that's the easy way to check. If there is no hole where Bendix can be seen,loosen bolts holding starter in place, move and shake starter,retighten bolts and try starter. CAUTION,do not apply power to starter while bolts are loose. If bolts are difficult to access, here's a different approach. With ignition switch off,put tractor in high gear then rock tractor by pushing-pulling a rear tire. It need's to be rocked hard enough so that cooling fan can be seen moving. Follow that with trying to start. If this make's the difference,you might replace the Bendix without replacing starter motor. Otherwise, you will know how to get it going next time.

 

[Fuddy1952]

It's a simple test: "4) now meter positive + lead on battery positive +. Negative lead on starter terminal.
Should be zero volts off & cranking. off 0, ignition in on position 3.49, crank 12.43"

From battery + he's measuring a voltage drop from there to starter. When solenoid is engaged then battery + goes through it to starter motor.
Voltage drop means bad cable, connection (corrosion) or solenoid.

 

[Jon@HannenFamilyFarm]

Thank you to everyone for your help. It is now up and running as it should be...

For future reference, ALWAYS CHECK YOUR CONNECTIONS! (and I open myself up to public ridicule, it is well deserved)

Long story short, it ended up being the new ground terminal on battery that was not clean (had black paint on the inside). Because it was a brand new terminal, I overlooked making sure it was clean and making good contact!

 

[Fuddy1952]