Ford 4000 Sparks off the Positive terminal when starting.

BDS2 · May 3, 2017

When I turn the ignition to start the tractor I get sparks flying off
the positive battery terminal and the battery drains. I recharge the
battery and disconnect the positive terminal of the battery.

To trouble shoot the issue I hook up jumpers from the positive terminal to the starter
and I get absolutely nothing. I would think it the starter
would turn over or I would get the huge spark again.

I am a novice to tractor repair but have a some electric background.
What am I missing? Could it be the battery? even though it will fully
charge after the sparking issue drains it.

Bought the tractor last year and it worked great except it did by it with a quick disconnect
because of battery drain when the tractor is turned off.

I am new here. Let me know if I am posting to the wrong forum. Thanks!

Xfaxman · May 3, 2017

Was there any corrosion on the positive terminal or the cable clamp?

Disconnect the negative cable, then check the resistance off the positive cable from the post to the starter terminal. Then check from the cable clamp to the connector at the starter terminal. the readings should be the same and near zero ohms.

What is the voltage reading with the test leads directly on the posts, not the cable clamps?

ovrszd · May 3, 2017

Sparks from either batter terminal when a load is applied (such as starting) is an indication of a bad cable connection to the battery.

Would have nothing to do with batter drain

Welcome to TBN.

Bear with us a bit. Someone will come up with a solution. If asked for more information, provide it.

BDS2 · May 4, 2017

ovrszd said:
Sparks from either batter terminal when a load is applied (such as starting) is an indication of a bad cable connection to the battery.

Would have nothing to do with batter drain

Thanks ovrszd and vfaxman for your replies.

I looked a little closer at the condition of the battery and I did find corrosion on the positive post
and also noticed what looked to be some surface acidity around the cells. So without further trouble shooting
I decided to go ahead and replace the battery. I pulled the battery and once I did that I looked around for
any damage to the battery cables. The main terminal cables looked good. I happened to notice on the way to the
auto parts store the date on the battery was 01/2008. It tested bad at the store even though my charger showed
fully charged at home. When I went to put the battery in I happened to look up inside towards at the wires going to the
instrumentation since there clearly visible on the side where the battery is housed. Oh boy! Something had made a huge
nest. I pulled the instrumentation panel and found a chewed off ground wire and a positive wire that was exposed.

I cleaned up the mess and taped up the ground wire and the positive wire and put in the new battery. I did not reconnect
the ground yet since I did not know exactly where it went to.

To make a long story short .... I replace the battery and the starter engaged with no more sparking off the positive terminal.
The battery was definitely bad and I am hoping that by permanently fixing the instrumentation wires I can eliminate the battery
drain and not have to use a quick disconnect. Thanks again!