4340 Electrical Problem

[cook37184]

First, some background information. 4340 with metal cab. Replaced key switch and charging indicator lamp last summer, then everything was working fine. Then, two weeks ago, the starter would not turn over, not even a click. Tried charging the battery, installed a new battery, even hooked jumper cables from my truck directly to the solenoid. Still nothing. Took the starter to a repair station, it worked fine when hooked up to the tester, so I don't think it's in the starter or solenoid. Installed a new starter relay anyway, just in case.

Alright, here's the interesting bit. I always disconnect the battery at night. After reconnecting it the next morning, I read 13.8 volts everywhere that I should be. Until I press the starter button, then I show no voltage anywhere except the battery terminals. I can also hear a faint click when I press the starter, it sounds like some type of circuit breaker is tripping. After disconnecting and then reconnecting the battery, the system is re-set, and I show voltage at all the proper places again. Over and over, same thing.

Is there a "circuit breaker" on the positive wire that runs from the positive terminal on the solenoid to the key switch? I can't find one. That's the only thing that makes sense, because after I hear the click, I no longer have power on that red wire.

All suggestions will be appreciated.

 

[diyfarmer]

That sounds to me like your master switch is burned out. it will still send enough power to work things until you press the button but not enough to start the tractor. It would be a regular enough error on them especially if it's one of them steel ones. Also check your earth strap isn't corroded.

 

[hala]

I agree it sounds like earth or masterswitch problem that can have the same symtom as the masterswitch breake the circut between the battey minus pole and the chassie. The solonoid takes about 50-60 amp initially and this current can turn out a bad masterswitch that will work again if it turns off-on but will not stand a high currant.

 

[cook37184]

Thanks for your suggestions. I spent a good portion of New Year's Day poking and prodding (and cursing) the tractor. I replaced the ground cable, which was slightly worn. No change. Then went through all wiring again, it still has the one "click" before all circuits are dead, requiring the reset by disconnecting the battery. I even bypassed the key switch by moving the + wire that comes from the starter , placing it directly into the starter button. Same thing, one click. However, this click that I thought was coming from under the dash is actually coming from the solenoid. I held my hand there while my wife pressed the start button.
Again, the solenoid and started worked fine at the auto parts store last weekend.
I was going to order a new solenoid today from Ridgeway in Arkansas, but they convinced me to go through the wiring again as they didn't believe it was a bad solenoid.

Maybe the rain will be gone by Saturday, and I'll begin searching again.

Once more, I appreciate your responses.

 

[hala]

Have you bypassed the main switch? Direct conection between battery and chassie will bypass the main switch.

 

[diyfarmer]

Yes indeed you haven't mentioned if you have by-passed the master switch as well??

You know you could by-pass the whole key and button to start it and just start it straight from the starter, at least you'd know the starter was good then.

 

[hala]

as farmer saying connect plus on the starter coming from the battery and the solonid. If it just click you have a bad plus or minus conection or a bad starter. If it starts the problem is the plus from the battery via key switch and starter button to the solonoid. There is no fuse in this line.

 

[cook37184]

To answer the questions above: I have bypassed the key switch, I have bypassed the starter button, and the clutch safety switch has been bypassed for decades.
I have tried shorting across the two large terminals on the solenoid.
Again, the starter and solenoid worked when taken to the repair shop and hooked up to the tester.
I'm usually quite handy at sorting out problems like this on my own, which is why it took me three weeks to ask for help here on the forum.
As someone stated above, there aren't very many parts in the starting system, but I have checked and rechecked in various combinations.
I remain quite baffled, but also appreciative of all the suggestions.
Meanwhile, I'll keep dragging out 5x6 rolls of hay with the truck

 

[diyfarmer]

You still haven't said you by-passed the master switch??? the master switch is not the key, it is on the earth cable between the battery and the chassis. There is not a whole lot left to try unless you have a huge earth that's taking your power when your trying to start.
If you used a big screwdriver to start by putting across the poles would start it unless the earth cable is not getting enough grounding. Are you sure the battery connectors are perfect, not corroded or cracked

 

[cook37184]

Sorry for the confusion, DIY. This tractor did not arrive with a "master switch", which are called a "battery disconnect" here on our side of the big pond. So, while that can't be a problem, it is a convenience I'm going to add.
If I don't trade for a New Holland instead

Spent some time between sleet and rain showers today, beginning at the battery and disassembling each connection to clean and apply "corrosion preventer" before putting it all back together. Also removed the starter again to make sure the flywheel would turn, thinking MAYBE a stuck engine might be to blame (see how I'm grasping at straws here?!)

While I had the starter off, I hooked it to the battery with jumper cables. nothing on the first try, even when bypassing the solenoid. Then I rotated the starter on it's axis 180 degrees, bypassed the solenoid, and the starter motor spun while the pinion extended. Possibly a bad connection within the started or solenoid? I'll know soon.

 

[hala]

Now it sounds like a carbon brusch problem. The solenoid gets its inrush current via the brusches if not it just click. Either worn out or stucked.brushes.

 

[hala]

Here is a better explanaition how the solenoid works and why it might just click.

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[chip]

I am having the exact same problem on my 92, 7745. Have you resolved the issue yet?

 

[diyfarmer]

I am having the exact same problem on my 92, 7745. Have you resolved the issue yet?

What's the problem with your tractor? did you try starting with a screwdriver at the poles on the starter?

 

[chip]

Yes tried the screwdriver charged the battery just like the other gentleman.

 

[diyfarmer]

Have you nothing at all? is it like totally dead? not a kick or does it even turn over

 

[chip]

Upon inserting the key, dash lights will light up but press the clutch then push the start button and you get one click the all is dead. Same symptoms as the other Gentleman and tried same remedies, no improvement. Just wondering if he replaced the starter and selenoid .

 

[chip]

Ok! I bought a new reduction gear starter on eBay for $85, shipped. It was smaller, lighter and bolted right up. I connected the wires and the engine fired right up. Happy Ending.

 

[cook37184]

Again, thanks to everyone for your suggestions.
Armand, I'm glad you got yours going again, and I have done the same thing to resolve the issue. I didn't go with the gear reduction starter though, just the direct-drive like original. Only $135 shipped to my house, so I couldn't pass that up. I had the original started rebuilt a few years ago and that costed $125, so a new one for $10 more seemed to be a good deal.

Hopefully this thread will help some others troubleshoot their starter problems.