Strange Electrical Problem!!

Papasmith · Oct 23, 2012

4500 2 wheel drive with 590 hours starts intermittently.

Sometimes, after turning the key, the dashlights just dim and go out.

I have cleaned and reconnected the battery cable and posts.
Cleaned and reconnected the battery ground.
Tried to make certain electrical connections were clean and tight on the tractor
The battery is almost new and fully charged.
I have checked the safety switch on the transmission lever and it works fine.
Found one ground that was loose and fixed. Tractor started fine 3 or 4 times then, it started doing the same thing.

Here's the WEIRD part. On two occasions when I tried to disconnect the NEGATIVE terminal, I saw a small spray of sparks. I looked around trying to find something positive that I could have accidently hit. Saw nothing. Took a small insulated wire, attached it to the negative and started touching around the area that my tool could have touched. Got nothing. Battery is clean, shows no sign of leakage.

The other weird thing is, once this happened, the tractor has started for about 4 or 5 times. However, the problem is going to come back. It will start a few times and then, then the tractor will start manifesting the same problem.

Does anyone have a ghost of an idea of what is going on?

Thanks,
Dave in NC

Cecil Stults · Oct 23, 2012

possibly your ign. switch coming apart internally. something in it is loose and touching the wrong thing.
does the switch positions feel "right" or mushy?

If you have a spark at the battery when touching the cable to the post then something is drawing juice. start disconnecting wires from things gen. lights, ign. switch one at a time and see when the sparks go away at the battery.

I am just guessing here.

Srb08 · Oct 23, 2012

If you have a spark at the battery when touching the cable to the post then something is drawing juice. start disconnecting wires from things gen. lights, ign. switch one at a time and see when the sparks go away at the battery.

I am just guessing here.

You are correct.
You can pull fuses, one at a time, to isolate the current draw.

JerryK · Oct 24, 2012

Odd about the spray of sparks.. like above post.. you would think you would have to have current draw to get a spark when disconnecting the negative. The cable lug could be failing internally [ which is a COMMON problem ], where the copper wire is crimped/soldered internally to the negative lug clamp. One quick test on starting systems is to split your problem in the middle to see which half is causing your problem. Turn the key to ON, then jumper from the big positive lug on the solenoid to the small start lug and see if it will try to start. If she turns over, then you probably have a 'little wire'/switch problem... and if she doesn't, you probably have a 'big wire'/battery problem. Unless, of course, your starter/solenoid is the problem.... Good luck, Jerry

Papasmith · Oct 25, 2012

Cecil Stults said:
possibly your ign. switch coming apart internally. something in it is loose and touching the wrong thing.
does the switch positions feel "right" or mushy?

If you have a spark at the battery when touching the cable to the post then something is drawing juice. start disconnecting wires from things gen. lights, ign. switch one at a time and see when the sparks go away at the battery.

I am just guessing here.

Thanks for your thoughts but, I forgot to mention that it is a new ignition switch which was installed to try and correct the starting problem. With the battery, I do not even have time to disconnect the terminal. I just get a good grip on the battery cable connector and, there is that light spash of sparks. Then it is gone. Much bigger than what you would expect if say there was a small draw on the battery like with a clock on a car. This doesn't happen everytime. In the 10 times or so that I have disconnected and reconnected the battery, it has happened twice. Also, battery does not seem to discharge even when left a week or two. I mean, I have never heard or encountered anything like this. I just can't figure it. Thanks for everyone's input.

JerryK · Oct 26, 2012

I still bet the corrosive gas coming from the battery has ruined your cable. The sparks are coming from the white pasty inside of the battery clamp where the copper wire used to be snugly crimped to the battery clamp. The battery fumies have gotten in there and deteriated the connection... durn fumies... Clean everything up and install a new cable... worth a try. And again, get some ' battery terminal spray ' and coat the new installation when you are done. Anyone with a top terminal battery should instictively think 'I must coat with wax' whenever they see a battery... When you get around to installing a new battery, and can find a side terminal battery that will work... even if you have to do some tray modification... go for it. It is not that hard to put new side terminal cables in. You can splice them into the old cables if they are too short.

Papasmith · Oct 26, 2012

JerryK said:
I still bet the corrosive gas coming from the battery has ruined your cable. The sparks are coming from the white pasty inside of the battery clamp where the copper wire used to be snugly crimped to the battery clamp. The battery fumies have gotten in there and deteriated the connection... durn fumies... Clean everything up and install a new cable... worth a try. And again, get some ' battery terminal spray ' and coat the new installation when you are done. Anyone with a top terminal battery should instictively think 'I must coat with wax' whenever they see a battery... When you get around to installing a new battery, and can find a side terminal battery that will work... even if you have to do some tray modification... go for it. It is not that hard to put new side terminal cables in. You can splice them into the old cables if they are too short.

Interesting idea. It would make sense because, as I mentioned, I was not, to my knowledge, hitting anything positive when taking off the negative cable. Those sparks had to come from somewhere and, in addition, though they appeared as sparks, they didn't have quite the look or sound of electrical sparks. I'll give your suggestion a try and get back to you and the community if it works. I mean, this was a real puzzler for me. Thanks again Jerry. It's good to have smart folks like all who have replied to help with these kinds of problems.

Dave in NC