Solenoid failures

[Slammin Sam]

I have an 89 B2, 5 speed, 145,000 original miles. After almost 50 years of driving, I had a solenoid failure that resulted in the starter not disengaging, cooking the starter. Luckily, the flywheel wasn't damaged. I was a few blocks from home so I ran into the garage, grabbed a wrench and disconnected the battery. I replaced the solenoid and the starter. The next day when leaving my shop the same thing happened! Once again I managed to pull the battery cable (not before it melted). New solenoid and positive cable and all seems well. My question, did O'Reillys sell me a defective solenoid or is there an electrical gremlin causing this? I wanted a Motorcraft, but they don't stock them and I took a Borg-Warner instead.

 

[jhammel85]

Honestly, It sounds like it's grounding out somewhere and cooking the solenoid. I know you probably did this but I would start inspecting the wires that come off it on the hot side and work your way to the battery. Hopefully you find one with some worn or pinched wires.

 

[wildbill23c]

Sounds like you have a bare wire somewhere shorting out. I'm about 99% sure of it. I had the same problem with my 84 Bronco 2. I went through 3 solenoids in 2 days. Then on the 4th solenoid as I was installing it, I dropped on of the washers as I was trying to get the wires connected so I was fishing for the washer and happened to see a wire that was bare, I thought well I'll fix that since I found it, then during that process I found a couple other wires that had bare spots, I fixed those, and finished installing the solenoid. This really had me pissed off for a while and wasn't driving the B2, because I had no clue what was going on. Its been about 5 months now and haven't had the problem happen sense.

Bare wires over there that are in relation to that solenoid will definitely cause the solenoid to short out and fry things. When it first happened to me and the thing kept cranking and the key was in my pocket I thought for sure something major had happened. Nope just a bare wire, and a fried solenoid and starter.

Thorougly check all of your wiring that goes to and from the solenoid, that includes the battery cables, and all the wires connecting to the solenoid. There's one or possibly more that have bare spots from rubbing on the metal around them.

 

[Beachbuggy]

I was having this problem right before my 4.0 swap and I believe the ignition switch was to blame. I had tried two different solenoids, swapped starters, and been through all the wiring thoroughly with no luck. I can't confirm it, however, as I swapped the complete system when I went 4.0.

 

[Slammin Sam]

I found that the wire from the battery side of the solenoid to the power distribution box on the fenderwell has some cracks/dried rotted area in the molded rubber connector, but shows no signs of arcing or grounding out. I checked the LMC catalog and don't see where it is offered. When I installed the starter I checked that wire and didn't see any breaks in it.

 

[PetesPonies]

If it truly is the solenoid at fault, smack it with a hammer. This will break the connection at the two contacts. Usually that is all a stuck solenoid needs.

 

[3rd Petal]

I've had the ignition switch stick on and not return to the run position and keep the starter engaged. I'd assume you tried turning it back a little to make sure that's not the problem though, just wanted to make sure

 

[Twister]

I just recently have started to have the same exact problem. My solenoid is also new as i was trying to chase down why my truck doesn't like to start if it has recently been driven. I would have to let it cool off for a little while or it would crank incredibly slow and kill the battery. I've been starting it with one had on the key and the other on the hood pull so i can disconnect it quickly. I have a spare start i keep meaning to swap on to see if the current one is on its way out. Will be watching this, hopefully you get it fixed.

 

[Slammin Sam]

I have been driving the B2 for about a week now without a problem. . When the Bosch solenoid took a dump my neighbor had an old generic solenoid still in wrapper. Not sure of the brand, but it only had 3 posts and wasn't marked "made in China". I talked with my brother back in Ohio. He has one of the largest independent garages in town. He felt it was definitely a defective solenoid, never uses POS Bosch parts! Suggested returning the Bosch to O'Reillys and have them order the Motorcraft I should have bought in the first place.

 

[OlBlue38]

starter solenoid

A lot of times low voltage to the solenoid will burn the posts inside the solenoid, also low voltage itself can cause the solenoid to stick . Do not just start replacing parts. Use a volt meter and check for voltage drop between components. It could be a weak battery.