# JD 6320 - won't start (Electrical?)



## Runningbare (May 16, 2018)

Hey guys - I have come again for help and you guys always come through! I have a JD 6320 cab tractor that recently has been inconsistent in cranking over. There were times that it would start right away and then other times I would hear a loud click from under the hood and nothing. I don't know if it was coincidence, but if I would hook up a charger to the battery if would eventually start with the turn of the key. But it has been getting more difficult to get it started and now it will not start under any circumstances - just a loud click. I was assuming that the battery was getting weak but that is not the problem.

So here is where I am at:

I am registering 12.5 volts on the battery and I pulled the battery the other day and had NAPA check the voltage and it checked out good even when put under load. I have cleaned all battery cable connections and have checked the ground wire connected to the block and checked polarity with ohm meter so I have good ground.

I have 12.5 volts on the hot side of the starter solenoid and get the same voltage on the other large terminal of the solenoid when the key is turned on; however, the voltage on the connection on the starter itself shows less than 1 volt when the key is turned.

And, I checked where the clicking noise was coming from and there are 2 large, round relays located near the alternator that I am not sure of their purpose as I do not have a schematic or manual. However, on the lower relay, the hot side reads 12.5 v and the other terminal gets a matching positive charge when the key is turned. I checked the other relay and it too reads 12.5 on the hot side but the other large terminal shows no voltage when the key is turned on. So I suspect a problem with that relay but I am not sure if that has anything to do with the starting system. Any ideas? Does anyone know if those are starter relays?

I was considering pulling off the starter but this tractor has a large loader support directly if front of the starter location and at this point I can't even visually see the mounting bolts for the starter much less put a ratchet on it. So I am trying to rule out everything else first.


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## glasswrongsize (Sep 15, 2015)

Low tech diagnostic approach: I use a small FFTT (Ford-Fine-Tuning-Tool AKA "Hammer") and peck on the starter near the back side of it. You don't need a 12 lb sledge and you don't need to beat the tar out of it...just peck on it a little. It sounds like the brushes in the starter may be getting worn and not making good/consistent contact. Pecking on it will often times get the starter working. Peck a couple of times, then try the switch. Peck a couple more times and try it again. IF it starts after pecking on it, you know your problem.


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## Farmerbrown2 (Sep 25, 2018)

Yup sounds like starter to me. I have seen this several times . The mechanic where I work had the starter rebuilt on my Hino dump truck still had same problem so we take truck to Hino dealer. They put a brand new starter on end of problem.


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## Runningbare (May 16, 2018)

I will try that.I tapped on it on the front but I will do the same in back.


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## somedevildawg (Jun 20, 2011)

I'll help you all I can, first off, it does indeed sound like a typical starter problem....however, in your text you said that the starter had no voltage when the key was turned on....did you mean when the key was turned "on" or did you mean when the key was turned to "crank"? Just not sure what you were saying there.....it shouldn't have voltage when the key is in the "on" position, only when in "crank". I don't think those relays have anything to do with the crank circuit......do you get interior lights and gauges? I assume you do, and like the others have said....sounds like a starter problem. If tapping on the starter doesn't prove successful, check for voltage at the starter and see if you have voltage, that will be after all other circuits.....if it's got voltage and no crank....it's a good bet it's the starter or the connection at the starter. Hth


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## Runningbare (May 16, 2018)

So yes...the connector on the starter showed less than a volt with the key turned to "crank" position even though I am getting close to 12 volts on the output side of the solenoid. Everything works inside to include lights, blower motor etc.


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## somedevildawg (Jun 20, 2011)

Ok.....now we are getting somewhere. I'll give you a hint, I know it's a PITA if you're using a VOM to check with, but if you haven't, use a standard test light, it's much easier  
Back to the problem....if I'm understanding you correctly, you have voltage at both sides of the solenoid on top of the starter when in "Crank" but the voltage at the starter is a no go? Remove that piece of 2awg cable (about 10" long) and check it real good, both sides of the cable......I seem to remember having a problem with the connection at the starter once in mine, idk... But it's definately a problem in the cable or connection. The starter will not turn over until that wire has voltage (12) beings you've already ensured a good chassis ground. that will save you some pounding with the hammer 
You've been experiencing a high resistance connection that has finally failed......


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## Runningbare (May 16, 2018)

Thanks for the info! I did try running direct current to the starter by using one wire from a set of jumper cables and touching one end to the starter leg and the other end directly to the positive post of the battery with the key in the on position. The engine turned just a little but not anywhere near enough to start the tractor. I could hear the starter turning and the engine turned just a little. Thats when I left it alone for the night.


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## somedevildawg (Jun 20, 2011)

What did you find today.....


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## Runningbare (May 16, 2018)

Sorry for the late follow up but I messed with the tractor by quickly turning key like 15 times and all of a sudden it kicked in and turned over. I live about 5 miles from the AgPro so I ran it over there and dropped it off. They didn't get to it for several days but they determined the starter was the problem. They put a new shop guy on it and he put nearly 8 hours getting the old one off and the new one on. The problem was that they were unable to remove the loader so he had to work around that. He had to work blind as you couldn't even see the starter bolts much less put your hands on them. Also the bolts were not hex head bolts but required a torx bit and one of those was rounded out. So it was a bear. The starter was about $500 and the shop manager just charged me for 3 hours labor so I got out of there for about $900. So they were good to me. It was a lot of cash but its done and the tractor turns over and starts immediately now. Thanks to everyone for their input. If the starter was hanging up, I sure thought I would have seen a current draw at the starter when turning the key. Go figure!


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## paoutdoorsman (Apr 23, 2016)

Glad you got her going runningbare


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## Tx Jim (Jun 30, 2014)

I'm glad you got it repaired BUT engine does not need to run for FEL to be removed. All that is required is an overhead lifting device.


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## r82230 (Mar 1, 2016)

You might want to consider this place if you ever want to buy a starter again.

https://www.tractorpartsasap.com/starter-bosch-plgr-18359-bosch-0-001-230-005-114712.html

At $169, you could have a 'spare'. Note: no labor savings, but even at $100 an hour labor rate, you would still have $400 in YOUR pocket.

I have had good success with the parts from ASAP.

Larry


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