Why do I keep replacing starter solenoid?

[whorrall]

I have a 1990 Johnson 40hp VRO outboard on a 16' Jon Boat. The motor starts and runs excellent except for one problem. About every forth or fifth trip out my solonenoid fails and has to be replaced. Seems to usually happen when I have been running the boat for a good while, then I shut it off, then when I go to restart it, nothing. All connections to the battery are tight and clean. This has happened today for the 3rd time in the past 2 months. Each time a new solonoid ($20) fixes the problem, until it inevitably happens again. Any ideas?

 

[wilde1j]

Re: Why do I keep replacing starter solenoid?

What solenoid??? Is it this one: 0395419 SOLENOID ASSY., BC it's not $20, it's almost twice that. If you're using an automotive solenoid, try the right one.

 

[whorrall]

Re: Why do I keep replacing starter solenoid?

What solenoid??? Is it this one: 0395419 SOLENOID ASSY., BC it's not $20, it's almost twice that. If you're using an automotive solenoid, try the right one.

Yeah, its that one. I pay $20, but I get a deal on my parts...

-edit-

http://www.marineengine.com/parts/j...manufacturer=Johnson&section=Electric+Starter

Here it is for 14 bucks. They're not expensive, but I just don't want to buy one every months.

 

[wilde1j]

Re: Why do I keep replacing starter solenoid?

Carefully check the light gauge wires for corrosion or poor terminations. Something is likely causing the solenoid coil to pull too much current when it's activated. I can't imagine any other failure so quickly.

 

[jtexas]

Re: Why do I keep replacing starter solenoid?

starter drawing excessive current?

 

[whorrall]

Re: Why do I keep replacing starter solenoid?

I just checked and a couple of connections were a little loose. Also, the lower unit low-oil alarm was disconnected. I reconnected it. Could this be what is causing the issue?

 

[whorrall]

Re: Why do I keep replacing starter solenoid?

starter drawing excessive current?

How could I tell? How could I fix this problem, if thats it?

 

[wilde1j]

Re: Why do I keep replacing starter solenoid?

starter drawing excessive current?

That would fail the contacts, but not the coil. Not sure what's failing.

 

[wilde1j]

Re: Why do I keep replacing starter solenoid?

I just checked and a couple of connections were a little loose. Also, the lower unit low-oil alarm was disconnected. I reconnected it. Could this be what is causing the issue?

Possibly. What is the failure mode? Solenoid coil (causes 'no click') or contacts?

 

[whorrall]

Re: Why do I keep replacing starter solenoid?

Possibly. What is the failure mode? Solenoid coil (causes 'no click') or contacts?

No click at all.

 

[Vic.S]

Re: Why do I keep replacing starter solenoid?

No click at all.

So it is the coil failing.

You could try a genuine OMC one !

Thin wires or poor connections would introduce resistance in to the circuit which would reduce the volts and the current so that is not likely to be the cause!

Your engine, I think, has a non regulated rectifier.. that would tend to overcharge the battery if running for long. Maybe your battery tends to charge to an exceptionally high voltage and that is causing the problem. Darned unlikely although you do suggest that it is something that occurs after a longish run.

Switch a light, spotlight or something fairly powerful, on for a minute or so before restating... just to see if knocking the battery volts down a bit solves the problem.

A different battery may behave differently if it is related to excessive volts.

Do you have a particularly large capacity battery?

I dont know if the battery type, ie flooded , AGM or gel would have any bearing on the matter

 

[Sixmark]

Re: Why do I keep replacing starter solenoid?

Any other time I have seen this it was caused by a bad solenoid ground, might be worth checking it again, even if it means breaking out an emery board and getting it looking pretty, don't worry we won't tell the wife that you broke into her stash of boards

 

[jhcreech]

Re: Why do I keep replacing starter solenoid?

sound like your cables my have high resistance or corrosion in side, if you have a batt load tester you can load test the batt through the cables and then load test the batt without the cables and see what the voltage drop is and you got to check each cable this way, if the cables are good you need to do a voltage drop test across the starter, if the brushes are worn excessively they can cause the amperage in the solinoid to increase, thus frying the solinoid, the voltage drop should not be more than a 200 milliamps any thing more their way to much resistance in the starting circuit...

 

[petryshyn]

Re: Why do I keep replacing starter solenoid?

Whorrall

Put a voltmeter across the 2 small terminals and measure the voltage when attempting to crank. If the voltage is lower than battery voltage while attempting to crank, its not the solenoid at fault.....

 

[Sixmark]

Re: Why do I keep replacing starter solenoid?

another easy method is using an amperage probe or if you are lucky enough to have one, an "in line aperage gauge" but they seem harder to find these days, using either you can check amperage draw in between each point.