Starter runs w/o solenoid in truck, not on ground

[Gene King]

Hello I've got a problem that's got me stumped. My starter will work perfectly normal testing it on a table, but you put it in the truck and even without the signal wire connected, just the main power connected, as soon as you reconnect the ground the motor wants to run. It's not even engaging the flywheel doing this because the solenoid's not energized to throw out the pinion. Anyway I've taken it on and off 1/2 a dozen times without finding the culprit. There's a spring between the plastic cap and the copper disc that pushes it away from the contacts, what am I missing?

 

[bucket]

That's odd. What is your exact testing method?

Might be time for a new starter though.

 

[SirRobyn0]

Well, I'm not sure. Pictures of the wiring connected on the truck and pictures of it being bench tested could give us clue. My gut instinct is that when you are tightening the positive connection on the start when it's in the truck the connection is swinging around far enough to hit the "signal wire". I've seen that happen before. A starter is a pretty simple circuit, ground, power and signal. The only two possibilities I can think of is a wiring mistake on installation or internal short.

 

[Snoots]

We need more info. The solenoid not only pushes the pinion out to the flywheel, it makes the main connection from the starter motor to the battery.

 

[Gene King]

@bucket jumper cables and a push button
@SirRobyn0 If that was the case the pinion would be engaging the flywheel
I'll go out and take some pics soon, cold in the northeast the last couple days

 

[Gene King]

@SirRobyn0 I fixed it actually, you gave me the idea, the power wire wasn't wrapping around to hit the signal wire, it was wrapping around to hit the contact that runs the motor on the bottom.
This was it after I fixed it, I saw that heavy duty insulation and didn't think about it I guess
Anyway thanks

 

[SirRobyn0]

@SirRobyn0 I fixed it actually, you gave me the idea, the power wire wasn't wrapping around to hit the signal wire, it was wrapping around to hit the contact that runs the motor on the bottom.
This was it after I fixed it, I saw that heavy duty insulation and didn't think about it I guess
Anyway thanks

Makes perfect sense, glad you got it taken care of!

 

[mtnmankev]

Makes perfect sense, glad you got it taken care of!

And the best part is, no space aliens were involved in the madness and mayhem.