Help with solenoid issue

Robb Webb · Dec 14, 2022

My son ordered a new solenoid for his L285 and I changed it for him since he currently has an arm in a sling.
Before taking off the old solenoid I took a picture of the wires to make sure I put them back correctly. When removing the old solenoid I had to wiggle it around to get it to disengage inside the housing. You can’t see how the end of the solenoid connects inside the housing but since it felt connected I pushed the notched end of the new solenoid into the hard to see slot in the stated housing. After reconnecting all the wires when I put the positive battery cable on it sparked and smoked a little and the starter or solenoid made a daily loud click. I quickly disconnected the cable. What did I do wrong?

rScotty · Dec 14, 2022

Not sure. But check connections first. The solenoid is an electromagnet that sends high amperage to the starter motor when it gets a signal from the key switch.

So it should have three terminals. Two are heavy, threaded terminals intended to carry power from the battery to the starter. One of those comes from the battery positive, and the other goes to the starter.

The third terminal is much lighter weight - that is probably the push-on terminal that I see in the picture. That push on terminal is where the wire from the key switch attaches.

You should be able to hook up all those wires and nothing will happen until you turn the key.

But if it smoked, that solenoid may be history. You can check it off the tractor by placing the solenoid case against the neg. battery terminal and jumping from the hot + of the battery to that small push-on terminal with a normal size wire. I use approx. 18 guage stranded like is everywhere under the dash.

If the solenoid is still good, each time you touch the hot + to the push-on terminal the solenoid will jump in your hand - the end piece will move, and it will make that sound. Hopefully all this will happen, so don't be surprised and don't get bit by that end piece when it jumps.

rScotty

lpakiz · Dec 14, 2022

Seeing the way the solenoid connects up to the starter drive, I'll bet that the U shaped device is not correctly engaged, and when you pushed the solenoid IN, it pushed the solenoids "armature" in, which in turn (inadvertently) connected the 2 big terminals.
As suggested, remove it and test by grounding the solenoid body, then energize the small terminal. It should draw the armature IN with a firm "click" which subsequentally connects the 2 big terminals.
Think of the 2 big terminals as an IN and an OUT for battery power to be carried to the starter motor field terminal.

The small terminal energizes the magnetic coil inside your solenoid, which does 2 things: it pulls on the U shaped clip thingy, which draws the starter pinion gear IN to engage into the engine flywheel. Then a fraction of a second layer, that same motion pushes a flat, copper, disc-shaped-round-like-a-washer piece of metal into contact with the 2 big terminals on your solenoid, connecting those 2 copper studs, thereby forwarding battery power to the starter motor windings.
I suspect you have inadvertently and prematurely connected the 2 big terminals by pushing the disc shaped washer onto them. Then when you attempt to hook up the battery cable, the big connectors think its time to send power on thru, thus the sparks.

Pretty sure you didn't damage anything and it will work fine when you get the U shaped device engaged correctly.