3010 diesel 24 volt system

[Superhornet]

I have an early 3010 diesel and it is hard to start as it does not crank over very fast and batteries dont stay charged. Starter and generator have been rebuilt installed new cables. I borrowed an old tech manual from a dealer and rang all the wires and found out the batteries are connected backwards according to their schematics. Their 3010 and 3020 all show solenoid to negative, positive to other battery negative either thru tractor frame or a separate cable and positive to side of starter stud. Mine is opposite. Is their book incomplete, what would happen if I switched it? Battery voltage rises when its running to appx 12.7 volts.
 

[55 50 Ron]

The 24 volt system has "floating" lines between the generator and starter. It doesn't use chassis as a current path for the 24 volts. So it sounds like something is connected wrong. These are difficult systems to understand and repair. Where are you measuring the 12.7 volts?
And do you have two 12 volt batteries or four 6 volt batteries. Somewhere you should be measuring 27 or 28 volts when it's charging correctly. If you have two 12 volt batteries and you are measuring across one battery, even 12.7 volts says the system isn't charging like it should. Provide more information please.

I've heard people say Deere made a big mistake with this design.
 

[FBH44]

I have a different color tractor, but I found running current thru the chassis really slowed down the starter. Did away with that, and ran cables directly from battery to starter, and BIG difference.
 

[Tx Jim]

[ET]

If you don't already have the jumper cable between the batteries get it. Along with that you need a fuse wire to ground the 12v side of the system. If you have any of those quik fix add on cable ends get rid of them and put on the right cable. You have high resistance someplace. After you try and start it look, touch and smell for something hot. When you touch it may be real hot. Guess how I know?
 

[55 50 Ron]

Sorry. I was thinking of the 2 Cylinder models with 24 volt electrical. Disregard my incorrect info.
 

[Superhornet]

It has 2 12 volt batteries and each read about 12.7 volts and about 25.5 volts across the series. Should the negative on one battery go to the solenoid and the positive on the other battery go to the post on the side of the starter as the book shows, ( mine is the opposite ) or does it not matter?
 

[55 50 Ron]

As I mentioned below, I'm not an expert on the new generation 4 and 6 cylinders so best not to give you wrong advice.
 

[Tx Jim]

[Tx Jim]