yanmar instrument panel short?

[ovation]

When I purchased the 1986 40' Hunter in the fall, I noticed the panel (type b panel) was loose, the cover was cracked and loose but thought nothing of it. Its probably been that way for years - I did weekly starts of the motor over the winter and had a few strange happenings, but could not pin point it to one thing. We had some heavy rain in the last few weeks.
Two days ago, I went to start the engine and the alarms were working, but the engine did not have enough power to turn over completely (tried and died). I checked the battery - all good and tried again. Still no luck. I had other maintenance - did a few jobs and then I left it to try/check next day.
I did notice my charger had stopped working ( coincidence?)-reset it
Yesterday I was back doing more jobs, I tried the engine one more time to try and track the situation. This time the engine tried to start. The starter was turning, and would not stop, even after the key was returned to the off position. May have burned out the starter. Once again, worked on other jobs, and then home to go on-line to do some research.
Today when I went back, I tried the engine and the alarms are no longer sounding, no lights, nothing. Once again the charger is not working - will not reset.
Anyone got an idea - could it be the panel/starter switch is shorting out - moisture or corrosion?

 

[Don S/V ILLusion]

Could be any of those things. The only way to find the cause is trace all wiring, remove and clean all connections and check voltages with a voltmeter. Guesses probably won't be helpful for you.

 

[Bill Roosa]

I would suspect that the battery charger and the starter problems are not related. If the starter "sticks on" and stays engaged while the motor is running that is probably a solenoid problem. The contacts get burned over time and then you try and start the engine in the cold and hold down the start switch for a long time (passing a LOT of current) and it welds the contact on the solenoid posts to the circular copper disk that moves with the solenoid core and bendix. If it "fixed itself" then I'd just keep an eye on it. The circular copper disk is supposed to spin a few degrees every time you release the solenoid so new copper is making the connection.
As for the alarms and not start now I'm thinking track down the alarms first as both circuits are powered by the same wire coming from the ignition switch. It would be odd for them to all fail at the same time and it be different problems. I'd work on the alarms because you can tell immediately that you fixed it as they will begin to sound and you don't have to work the solenoid and start and stop the motor...... just easier to start there.
No idea on why the BC would trip. Perhaps the marina power??

 

[Mike Bailey]

I have had similar problems several times over the years. You must protect the electrical system from water. Fix water leaks now for sure. If there is a lot of corrosion assume it will be problematic and service all the connections, one at a time. There should be a good schematic of the electrical system in the Service Manual, if you can find one. The starting circuit shouldn't be very complicated. Check one thing at a time with a good multi meter. Give yourself at least a good whole day to work this out and keep track of the results on a note pad. It would be a good idea to copy the starting schematic on paper so you can make notes as you go. You will figure it out and have the knowledge for the future. Good Luck.
(PS.I would check the ignition switch early on)

 

[wufibugs]

Not sure if its related but damaged cockpit panels are usually the result of increasingly stubborn engine kill cables. As above have suggested, pull it out and check the wiring for corrosion or connection issues. Then replace the panel. You can solve the root problem by renewing the cable, going electric, or moving it off the panel.

 

[Charles Erwin]

There is a fuse (30a) in an inline fuse holder. This fuse holder should be at the rear of the motor in the motor-to-panel wiring harness. If this fuse is broken then you will have no power to the instrument panel whatsoever. Nothing will work.

As for intermittent starter problem check the battery positive and ground connectors at the battery and the motor ends. Also check/clean connectors in the motor-to-panel wiring harness. There are a pair of these connectors (if the wiring harness has been extended there will be two pair) and they will be near the inline fuse holder. It is possible the key switch is bogus/corroded/decayed. If so, then all you need is a new key switch.

The starter is engaged by a separate push button - not the key switch itself. If the starter will not disengage the push to start switch may be the problem.

Charles