Starter solenoid shorting/drawing current?

I have had a fairly typical problem with my 98 V6 Tacoma that a lot of Toyotas seem to have - intermittent failure to start with a click under the hood, but no cranking. I cleaned up the battery terminals a few months back and it went away for a while, but it's come back and is a lot worse, sometimes requiring 5-10 tries to get it to start cranking - once it starts to crank, works great. So, after reading up on this, I decided to try a couple of things, suspecting the starter solenoid.

I first found that when I was cranking and just getting the click, the battery posts were still reading over 12V. I read that this should drop to ~10V or so for the starter load, but not a lot lower, or it suggests a bad battery. I then pulled off the main starter power cable which was rusted up pretty good, cleaned up the nut, stud, and cable end, and put it all back together, thinking this might help.

This is the strange part - when I went back to connect up the battery, I had violent sparking, and the wire down to the starter got really hot. The only thing I can think is that the solenoid has somehow seized in a position where it's now drawing power even when the ignition is off and not energizing the solenoid? With my battery and starter wire connected, nothing works in the car and the wiring heats up fast suggesting a short - didn't leave the battery connected like this more than 10 seconds.

To double-check the starter's influence, I disconnected the main starter wire, and then I could connect the battery without any problems, all accessories worked as normal, and I confirmed that the starter relay in the fuse box is clicking on and off as it should.

At this point, I am not sure what tests I can do on the starter, since all the voltage drop tests require having it connected, and it is clearly not safe for me to connect the battery in this state. Should I be pulling the starter and expecting to find a jammed solenoid? Any other ideas before starting that painful job?

Thanks,
Colin

 

Can’t comment without looking however here’s my two cents. Intermittent starter clicking is an indication of any one of the following; Weak battery and/or terminal connection or a failing starter. If your starter gave you 140,000 miles, its time for a rebuild or a new one. However, many are known to last longer.

When this occurs next, try a jump start. If it works, you should have your battery tested for the required cranking amps. If it still does not start, disconnect our starter solenoid and attempt to start by “shorting” the two starter terminals with a piece of wire. If it does, you know your solenoid is defective. I don’t understand why your starter wire is getting so hot and yet not blowing the fuse.

Remember a stuck starter can be released by rocking your car back and forth while in gear. This can be done with a 70-80% success. However, rocking a truck isn’t easy. A clicking starter is an early warning system for impending starter problems.

Please let us know what you find.

 

Well, 130K miles - good guess

The problem I have since cleaning up the main lead to the starter is that I can't connect the battery anymore. Even with everything off, I get violent sparks and a hot wire to the starter, so until I figure that issue out, I can't do much else. Is it possible that the starter could get stuck in a way that it's not cranking, but it's drawing power off the battery?

Other than this issue, every other symptom points to the classic bad contact problem that seems to afflict tons of these starters, so I was preparing to do that. But I don't see how they would cause the starter to get stuck drawing power.

Thanks,
Colin

 

I’m not familiar with your truck but basing this on my experience with starters. I cannot understand how there could be a power draw from your starter if your ignition is off. Can’t comment without looking.

I suggest your disconnect all wires from your solenoid switch. This should allow you to connect the power leads to your starter and still start with the shorting method. If you have an Amprobe or clamp-on meter on your starter power lead, you may be able to determine your problem with a little ease. Where do you live?

 

I take it that your power leads feed the solenoid directly. If this is the case, there's little you can do to trouble shoot. You can't "short-circuit" start it either. You'll need a new/rebuilt starter.

 

Attached photo says it all.

After more reading, I suspected that in the process of taking off and reinstalling the main lead, I may have overtorqued the stud. Sure enough, pulled the starter and the battery side contact was a mess - it was so thin that there must have been very little resistance to spinning the square head copper bolt around, mangling what was left of the contact with it.

Attached photo is probably a great example of what can go wrong.

So, I clearly need new contacts, and I'm pretty sure this is indeed the problem. Also, good lesson for others - when you see all the talk about checking connections, it's real easy to make a marginal starter a lot worse in the process.

It also looks like I need a new battery side stud, and the red insulator. The red insulator in particular looks like it's not in the kits - does anyone know a P/N for that part? I can't find it online.

Thanks,
Colin