886 starting help

[cjfling]

This is a general starting troubleshooting issue. My 886 won't start most of the time. When you turn the switch to the on postition the first time, the normal dash light comes on, but when you try to start it, nothing happens and the light goes out. I get 12.3 volts from both batteries when they are connected and disconnected. I'm going to get them load tested, but assuming they are good, can I bypass the starting (key) switch to rule it out? What I want to do is use jumper cables, clamp one black end to the negative battery post and the other to the tractor's frame. With one positive clamp to the batteries positive post and then touch the other to the positive side of the starter's solenoid long enough to start. Let me know if I can safely do this. Also let me know any other troubleshooting ideas you might have.

Thanks in advance,

Jason

[pedalstomper78]

It sounds liek you have a switch or a starter problem. Do you hear a click or anything from the starter? Are you getting the 12v to solenoid of the starter? (Not from the battery positive....from the key switch). The problem is if you just "jump" to the positive battery terminal, you've eliminated the starter as a problem, but there's a lot of electrical components between point A and point B. Do you have a wiring diagram?

[cjfling]

It sounds liek you have a switch or a starter problem. Do you hear a click or anything from the starter? Are you getting the 12v to solenoid of the starter? (Not from the battery positive....from the key switch). The problem is if you just "jump" to the positive battery terminal, you've eliminated the starter as a problem, but there's a lot of electrical components between point A and point B. Do you have a wiring diagram?

Thanks for responding to my post. Yes, I suspect a switch or starter problem. No click. That is why I'm trying to bypass the switch to isolate the problem on one side or the other of the switch. Then I can concentrate on all the components between A & B (with B being the switch). If that doesn't help, I'll move on to the starter and components between B & C (starter). Yes, I have a condensed shop manual with a wiring diagram. We'll see if I can make heads or tails of that, if need be. While reviewing the manual, I also saw that it has a starter safety switch that can be adjusted. The thing in the back of my mind, I'm just puzzled why the light (either oil pressure or coolant, can't remember) comes on like normal on the first start attempt, and then not again until the next visit.

Thanks for your ideas.

[pedalstomper78]

If you have a Volt/Ohm meter, test the key switch itself. I don't know what all interlocks may be on that tractor, but there could be a clutch, neutral, gear, etc safety switch that went bad causing the issue. If you can scan some of the diagram, I'm willing to give some good points on where to start. Electrical diagnosis is always a fun challenge for me......well....at least when it's someone else's. lol

[cjfling]

I'll do you one better and scan/post the wiring diagrams tommorrow. Be later in the week until I can try the volt meter on the switch. Thx

[cjfling]

Like I said, the manual I have is a condensed service manual and covers about 12 tractors from around 3 series. The labels on the attached images don't say 886, but I assume it's the same for the 886 and other IH tractors covered in this manual.

[pedalstomper78]

I guess my first big question is do you have 12v to the pushbutton for the starter and when you push the button, does resistance across those two terminals go to 0?

[cjfling]

My model doesn't have a push button, but a key switch for starting. The tractor isn't where I live, so sorry that I'm not able to answer these questions quicker. I plan to check on that in a day or two and will get back to you. Thanks

[pedalstomper78]

Hmmm....seems as if there may be more differences between your tractor and the wiring diagrams then. I'll see what I can come up with in the next few days also...

[cjfling]

Success! I got the batteries tested and one needed a charge. I charged them and went out do some testing. I probed around on my key switch. I got .03 ohms resistance on the switch and then installed the batteries. I could get 12v to the switch, but with the switch in the start position (not run) I couldn't get 12v on any other terminals on the switch. This didn't make sense to me. With the tractor in neutral, I manually depressed the starter safety switch that is normally depressed by the clutch, but still no 12v on any of the other terminal on the switch. I decided to move on and get access to the starter and noticed a wire lose on the solenoid. After carefully tightening that nut, the light that normally comes on when you first turn the key to the run position without starting came on. The tractor cranked right up. I was just about to try the direct application of 12v to the solenoid to bypass the switch and was glad to not have to try that. Thanks for your help and willingness to help.