John Deere 430 slow cranking

Need help
Have John Deere 430. Cranks really slow. New 6 volt battery and had starter rebuilt. Still doing same thing. Cranks really slow and doesn?t start easily. Pulls starts easily. Rechecking wire connections. Anything else?

I have run into a similar issue before on another brand of tractor. Does it crank faster with the ignition turned off? If so you?re timing is probably just a touch too early. This makes it very hard to crank (and consequently quite slow) but starts well with a tow. Best of luck, Sam

Make sure its got the 6 volt battery cables, and not the small ones for a 12 volt.

Low voltage across the coil while cranking causes weak or no spark and no start .
Your tractor has VD somewhere . Use a voltmeter and find the high resistance connection that is dropping the voltage .

Be sure you have a good ground connection to the frame of the tractor.

I had a 440 crawler loader with a backhoe. It was still on 6 volts. That large crankshaft driven hyd. pump really added some drag. Mine always started good. To do this I used large welding cable for battery cable. Those offered a heavy duty version of the starter that has 4 full field coils in it verse most that only had 2 field coils and 2 empty spots for 2 more. Be interesting to know what yours has ?

The FIRST thing I would try is to inspect (carbon or burning or corrosion) remove, clean and wire brush and re attach EACH AND EVERY BATTERY AND STARTER AND ANY STARTER SWITCH/SOLENOID AND GROUND CABLE.

Make sure battery is well charged and its best if you have say 0 or even 00 Gauge battery and ground cables. You need a good clean tight frame ground cable connection and if possible if its on or near the starter itself is better then a thin wimpy rusty sheet metal ground location.

I have seen battery cable ends that look fine but underneath they are burned or loose or corroded. A thin wimpy 4 gauge automotive ground cable drops too much voltage, at least 1 gauge better yet 0 or 00 battery and ground cables are better on 6 volt systems

Starter solenoids or mechanical push start switches can get burned and corroded and drop voltage also causing slow cranking even if all above is fine. If its possible to check voltage direct on the starter when cranking that tells a lot. Starting at only 6 volts you cant afford to drop to much across a faulty resistive cable or connection or switch or solenoid

A good heavy duty high CCA battery is a must

John T