Early 90's 90HP Mercury Outboard Starter stays engaged when battery connected

[stonedv8]

I have an early 90's model 90HP mercury outboard. It has 3 solenoids with tilt, trim and starter solenoid.

I recently took it out and it cranked when launching fine, but after running a few minutes and cutting it off all I got was clicking from the solenoid, but the starter would not turn over. I had a jump box with me and was able to jump the starter and it cranked fine. After diagnosing this I assumed the starter solenoid was bad and so I found one local and replaced the solenoid. After replacing it the motor started fine, I tested it a few times and then took it back out on the water. Everything seemed perfect.

After cutting the motor off I sat a few minutes in the water enjoying the view and then tried to crank it, this time same clicking noise and finally I could hear the starter spinning with the key off, and out of the ignition. So I disconnected the battery and reconnected it, this time it engaged the bendix and cranked the motor. I got back to my wet slip and cut the motor off with the key but the motor was still spinning. Again, I disconnected the battery. After waiting and let it cool off a few minutes, I tried reconnecting the batter and it instantly tried to turn over the motor. The whole time the key was out of the ignition.

Did I get a bad solenoid that worked temporarily and is now welded in the permanent "on" position?

Here is a link to the solenoid. Mercury - Quicksilver Starter Sl Solenoid Step Base 89-96158T - Solenoids - JMSOnline.net Marine Supply and Boating Store

 

[mercurymang]

Re: Early 90's 90HP Mercury Outboard Starter stays engaged when battery connected

Possibly. Could also be an issue with your key switch. Only way to really tell is figure out a way, next time it happens, to disconnect the ignition line (yellow wire i think) to the solenoid and see if it continues. If it does, then the problem is likely the solenoid. If not, it's your key switch.

 

[stonedv8]

Re: Early 90's 90HP Mercury Outboard Starter stays engaged when battery connected

Possibly. Could also be an issue with your key switch. Only way to really tell is figure out a way, next time it happens, to disconnect the ignition line (yellow wire i think) to the solenoid and see if it continues. If it does, then the problem is likely the solenoid. If not, it's your key switch.

Awesome, thanks for the reply, and that was my only other idea was the key switch. Knowing now it is the yellow wire, I remember that wire and it would be fairly easy to disconnect to determine if it was the switch or not. Just having these issues it seemed odd a brand new one would do this.

I am an Atv and motorcycle mechanic by trade so the basics I could figure out but I couldn't wrap my head around a brand new one giving me this issue and not something else causing a failure as well. Thanks for the quick reply, will be at the dock again tomorrow after work trying to figure this out. Have a big Labor Day weekend planned.

I did buy 2 of the solenoid a when I found them locally, since the tilt and trim use the same ones, figured I would have a backup. So if it is the solenoid, I have a spare. If it is the key switch, guess I could always hook up a toggle switch off of the key wires to get me by for the weekend.

 

[MH Hawker]

Re: Early 90's 90HP Mercury Outboard Starter stays engaged when battery connected

It sounds like the main power lead and the starter lead are touching at the solenoid or as you suggested the solenoid contacts are welded closed.

 

[stonedv8]

Re: Early 90's 90HP Mercury Outboard Starter stays engaged when battery connected

It sounds like the main power lead and the starter lead are touching at the solenoid or as you suggested the solenoid contacts are welded closed.

Good point, I did not think about touching wires. Everything was going good until I ran it out on the water. That's when it started staying engaged, maybe a wire moved and now they are touching.

I am at work now, again when I get off tonight, I am going to run by and work on it some more.

I dont know of anything, but do you guys know what could kill a starter solenoid? If maybe I have an underlying problem that killed the first one and now it has killed this one? Just something else for me to ponder on here at work.

 

[stonedv8]

Re: Early 90's 90HP Mercury Outboard Starter stays engaged when battery connected

Just got back.found the problem, it seems you both were correct it was a pinched/touching wire. Found it right away after removing the cover. The wire had gotten pinched under the cover and had worn through and was touching the starter wire.

Guess I was so disappointed in my repair I was blinded until I tried seeking advice.


Thanks again.