Starter engagement!!

[95OBSMan]

95 GMC RCSB 5.7 TBI

So the last 3 weeks I've been doing mechanical work to the truck, started with a coolant leak on the intake manifold, removed TBI unit cleaned, injectors cleaned, and reassembled and installed on intake, removed all A/C compotants and replaced w/ new except for evaporator.

Replaced radiator, both hoses and water pump.

Discovered oil pan leak, replaced that, in which I had to remove the Y pipe assembly as well as remove the starter for better access to the bottom of block for cleaning, cleaned all items and replaced, saw no signs of bad wiring going to starter or the knock sensor.

Double checked everything I touched for proper torque and that all plugs are plugged in where they go, finished the muffler job, lower truck down, double check all fluid levels, all there is to do is attach battery cables and prime fuel pump and look for fuel leak, well I attached the + side first to battery terminal and when I just touched the - lead to battery terminal the starter engages and turn the motor over, ignition switch is all the way back in the off position and the key isn't even in the switch!!! I put the small gauge "purple wire" on the only post that it fits on, and the RED wire to the post where it goes both on the starter solenoid.

Anybody got any idea what the heck I've done wrong!? I don't get it, I put everything back where it came from, the truck started good and ran fairly well... Thanks for any thoughts or ideas on this, I just don't get it...

 

[HotWheelsBurban]

95 GMC RCSB 5.7 TBI

So the last 3 weeks I've been doing mechanical work to the truck, started with a coolant leak on the intake manifold, removed TBI unit cleaned, injectors cleaned, and reassembled and installed on intake, removed all A/C compotants and replaced w/ new except for evaporator.

Replaced radiator, both hoses and water pump.

Discovered oil pan leak, replaced that, in which I had to remove the Y pipe assembly as well as remove the starter for better access to the bottom of block for cleaning, cleaned all items and replaced, saw no signs of bad wiring going to starter or the knock sensor.

Double checked everything I touched for proper torque and that all plugs are plugged in where they go, finished the muffler job, lower truck down, double check all fluid levels, all there is to do is attach battery cables and prime fuel pump and look for fuel leak, well I attached the + side first to battery terminal and when I just touched the - lead to battery terminal the starter engages and turn the motor over, ignition switch is all the way back in the off position and the key isn't even in the switch!!! I put the small gauge "purple wire" on the only post that it fits on, and the RED wire to the post where it goes both on the starter solenoid.

Anybody got any idea what the heck I've done wrong!? I don't get it, I put everything back where it came from, the truck started good and ran fairly well... Thanks for any thoughts or ideas on this, I just don't get it...

If the purple (ignition) wire is touching the big wire from the battery, as soon as the battery is fully connected...it will activate the starter.
I had this happen on my '90 square body Burb, got that battery disconnected and got under the truck to disconnect the wires and check it out. Sho'nuff, they were touching. Doesn't take much, either, just enough to pass current.
Some of the solenoids are made with a partition fence on the solenoid cap, that goes between the terminals and keeps them from making contact. Sometimes the terminals and wires are bent in a manner that prevents them from touching. When I replaced the starter on Rawhide, my crew cab, I took the wires loose before I unbolted the starter and reconnected them AFTER I got it bolted up to the block. Doing it this way, keeps the starter from dangling by the wiring harness (which is not a good thing to do anyway!).

 

[95OBSMan]

Thanks HotWheelsBurban! I'll bet money thats what I got going on, I'm guilty of letting that starter hang by the wires, I thought I had the nose of the starter supported by the flywheel, left it like that for almost a week b4 I could get to work on it again, should've known better than that, and I just bolted the starter back up thinking I don't need to check the wires, WRONG!! I'll have to get back under there and recheck them, bet that purple wire is either touching the + terminal or really close to it as you said. Thanks much, I really appreciate the heads up, can't wait to hear it running with the new muffler installed, crazy how a new muffler can get ya all worked up!!

 

[CumminsFever]

A new muffler is a great reason to go in town for a cup of coffee!
A stuck starter is even more annoying when it puts a stop to the plans.
Yes, I would vote the solenoid got cracked as it hung by the wires. I don't mind hanging the old starter by the wires when replacing a junk one, but not a good idea on one you care about.

 

[95OBSMan]

A new muffler is a great reason to go in town for a cup of coffee!
A stuck starter is even more annoying when it puts a stop to the plans.
Yes, I would vote the solenoid got cracked as it hung by the wires. I don't mind hanging the old starter by the wires when replacing a junk one, but not a good idea on one you care about.

Yes sir, nothing like a new muffler and a quick run into town and the coffee is a bonus, the sound is just what I thought it would be, gotta figure out how to post a video of it, looks like I'm going to have figure out how to do a Utube video of it.

HotWheelsBurban, you and CumminsFever are correct the purple wire was making contact with the main + lead and causing the starter to engage when battery leads are hooked up to the battery, the starter was the factory one and being 28yrs old the black plastic had crumbled which I think was what they called bake-o-lite an insulator for the starter solenoid, replaced starter and had to repair purple wire with a new ring end and some heat shrink and good to go, she fired right up and runs really good, thanks again for the heads up on that!