JD 310SG starter going out? Battery?

[Armymutt]

Recently I've noticed my 310SG is hard to start. Not as in cranking and won't light, but no action from the starter. When I turn the key to ON, I hear the first relay close. When I turn it to the Start position, the second relay closes, but the starter doesn't crank. This goes one for various numbers of attempts. Is my starter going bad? Is it the battery? I left the disconnect on a week ago and drained the battery. Put it on the charger and got it back to 13V. The problem was occurring before this though.

 

[HarleyHappy]

May be your contacts for the inside, some you can sand, some you can flip.

 

[Armymutt]

May be your contacts for the inside, some you can sand, some you can flip.

Can you give me more details on this? Are you talking inside the starter?

 

[edgephoto]

A few measurements you can diagnose this.

 

[berky]

Could be a weak battery, bad electrical connections or ground strap, but my best guess without seeing any test data would be a dirty or burn commutator inside the starter motor. Easy enough to take it apart and fix yourself or just take it to starter rebuild shop if you don’t feel confident. While your in there also clean an re-lube the bearings

 

[Delmer]

like edgephoto says, you can easily check the voltage going into the starter solenoid and out of the solenoid into the starter, and figure out from there what's going on. Make up some test leads to a voltmeter/multimeter in the cab and hold it to start a couple seconds to get a reading. That will tell you if it's the solenoid contacts, or internal to the starter like Berky mentioned.

The starter solenoid can usually be taken off the starter without removing the starter from the engine. Remove the ground cable at the battery first! You can take apart the solenoid, clean, flip, whatever the contacts need. Might be able to find new contacts. Almost certainly can find a new solenoid so don't be too worried about ruining the solenoid taking it apart. Plenty of youtube videos showing how to clean up or switch contacts, just find one with the same brand as your starter.

 

[excavator]

The second relay is under the panel by the fuses in front of the steering wheel. Check to make sure there is voltage going through when it clicks. Just because it clicks doesn't mean it's working.

 

[edgephoto]

Two words....voltage drop.

Measuring voltage is not a good test.

 

[Armymutt]

After some tests with the voltmeter and accidentally turning over the engine by jumping the fault, I found the problem. My starter is a remanufactured one that doesn't match any of them in the JD book. There are three external connections on the solenoid portion, which is on the bottom of the starter. That made it a lot of fun. I pulled the back plate off and looked at the contacts inside. They were a little discolored. The copper ring around the plunger was also discolored. Scrubbed everyone with fine steel wool until relatively shiny, reinstalled, and it fires up reliably now. The copper ring on the plunger is a bit pitted, so I might start looking for a replacement, if such a thing exists.

 

[HarleyHappy]

You won’t have to worry about it for the next decade, good job.