670 Will Not Start

g huns · Apr 9, 2011

I went out today to start up my 670. I had removed the battery in the fall(brand new in October) and stored it in my heated garage this winter. I put it on the charger yesterday just to make sure it was good to go. I cleaned up all connections and put it in. The tractor wouldn't start. I pushed it out of the barn and into the garage and got out the trusty multi-meter. Battery has 13V, the starter red wire has 13V. When I turn the key to "on" the volts drop to 2, when I turn the key all the way the volts drop to 0. I removed the ground cable from the frame and cleaned and nothing changed. I was wiggling and jiggling wires on the right side above the brake pedals while holding the key on and it turned over for just a second once. I am no electrical troubleshooting pro so any advice would be appreciated.

RoyJackson · Apr 10, 2011

Was the starter cranking? And, was it cranking fast enough? Did you hear any clicks (like the starter bendix)?

The easiest thing to do is jump off a known good battery and see if it starts then.

I think your battery is shot though. Brand new in October 2010...should still be in warranty.

But, see how jumping works...

Egon · Apr 10, 2011

Keep jiggling the wires and follow up where they come from and go to.

g huns · Apr 10, 2011

I came out this morning and unhooked the battery, still checks 13V. Hooked it back up and when I turned the key to on, the lights on the dash come on and when I turn the key all the way I get one click from the starter and the lights go out. I also have it hooked up to my big battery charger set to jump start. i think I'll remove the starter and put it in a vise and jump it to see what happens. I have never done that before though. Do I hook the positive battery terminal to the post where the big red wire goes and jump to where the small white wire plugs in?

Egon · Apr 10, 2011

Could that click be the fuel solenoid opening??

g huns · Apr 10, 2011

I know it's not the fuel solenoid as mine don't work, at least not plugged into the tractor. But I'll worry about that later. I just hooked it up to our JD 425 and pull started it and it fires right up. Just about made my 14 year old boy crap himself though. I figured the front end of the 425 would stay down when I dumped the clutch since it still has the snowblower on it. I was wrong. Only came up a few inches, just enough to make his eyes get real big. I let it run for a while and then shut it off, tried to start it up and same thing. I am going to pull the starter and try to see what's up.

RoyJackson · Apr 10, 2011

Dead short somewhere...
Do you have the wiring schematic? I do have a 670 service manual and can get a schematic for you, if needed.

g huns · Apr 10, 2011

I tried jumping the starter and couldn't get it to do anything. Torn it all the way down, nothing looked bad, cleaned all the brushes with emery cloth but it's still not doing a thing. I'll take it to a guy tomorrow who rebuilds them and have him give it the once over.

RoyJackson · Apr 10, 2011

g huns said:
I tried jumping the starter and couldn't get it to do anything. Torn it all the way down, nothing looked bad, cleaned all the brushes with emery cloth but it's still not doing a thing. I'll take it to a guy tomorrow who rebuilds them and have him give it the once over.

Yeah...well, that's an old starter. Haven't built 670's since 1998, I guess.
Good luck getting it worked on or rebuilt. Keep us posted on how you make out.

jd110 · Apr 10, 2011

I hate to say after you have gone to so much work removing and disassembling the starter, but I suspect you have a bad battery cable. The starter can't work if the voltage is droping to 2 volts.

grsthegreat · Apr 10, 2011

jd110 said:
I hate to say after you have gone to so much work removing and disassembling the starter, but I suspect you have a bad battery cable. The starter can't work if the voltage is droping to 2 volts.

you might be right..ive had that happen to a car i had before

RoyJackson · Apr 10, 2011

jd110 said:
I hate to say after you have gone to so much work removing and disassembling the starter, but I suspect you have a bad battery cable. The starter can't work if the voltage is droping to 2 volts.

Maybe, but he did jump right to the starter...bypassing the battery cable (that's the way I read the post).
We'll get some feedback from g huns in a day or so...

grsthegreat · Apr 10, 2011

RoyJackson said:
Maybe, but he did jump right to the starter...bypassing the battery cable (that's the way I read the post).
We'll get some feedback from g huns in a day or so...

oh ya, i missed that the first time i read thru here.

g huns · Apr 22, 2011

Ok, i'm finally back to working on this thing. I took the starter to a repair shop and they gave it a clean bill of health. My ground cable on my workbech where I was testing it was bad which is why I couldn't jump it. I cut the end off the positive battery cable which was really nasty looking and replaced the clamp. It still behaves the same way. I removed the panel below the dash that they ignition switch is attached to. I unplugged all the connectors except the one to the dash light and turned the key, the lights stayed lit up so I plugged them back in one at a time until when I turned the key everything went dead. The plug that did the trick is the largest one which is connected to a pigtail hanging out of a large black box. I have no clue what it is but I plugged it part way back in and wiggled it while turning the key and it turned over a couple of times but when I plugged it all the way in it all went dead again. The plug has a large rubber cover on it and when I pulled it back the plug is very brown like it's been pretty hot. Any idea what this box is and what it does? I pulled it apart. It houses a circuit board that when removed has nice black mark where a resistor connects to it. I can't wait to call and find out what this thing cost.

Tractor Pilot · Apr 23, 2011

g huns,

Here is part of an electrical system schematic for the 670 that shows the key switch and what the wires go to. Hope this helps.

Bruce

g huns · May 3, 2011

Well my electronics nerd appreciated the schematic. I gave it to him instead of give Deere and Co another $300. The board had a couple of burnt spots and after testing there were some capacitors and a resistor that needed replaced. He took care of these things but when I plugged it back in and tried to start the tractor, same thing. One click and dead, no power again until I disconnect the negative battery cable and reconnect it. I'm lost as to what to do with it next.

cgutenschwager · Aug 7, 2020

g huns said:
Well my electronics nerd appreciated the schematic. I gave it to him instead of give Deere and Co another $300. The board had a couple of burnt spots and after testing there were some capacitors and a resistor that needed replaced. He took care of these things but when I plugged it back in and tried to start the tractor, same thing. One click and dead, no power again until I disconnect the negative battery cable and reconnect it. I'm lost as to what to do with it next.

Well I know this is an old post, but I'm hoping someone can assist with my current project. I am working on a 670 that had been invaded by mice - they filled the area with all the electronics with their nest and chewed a few wires. All has been cleaned and repaired (I think). My issue is the fuel solenoid - it retracts when the key is turned, but then closes after a couple seconds. I have checked the power with my meter and I have 0 volts (ground?) 12V and 12v that drops to 6v on the third wire. Is this correct? Maybe the wrong fuel solenoid had been installed? (it was changed by the owner).

Thanks for your help in advance.
Cory