• Untitled Document

    Join us on March 29rd, 7pm EST

    for the CBEC Virtual Meeting

    All EYO members and followers are welcome to join the fun and get to know the guest speaker!

    See the link below for login credentials and join us!

    March Meeting Info

    (dismiss this notice by hitting 'X', upper right)

Yanmar YSM8 troubleshooting

csoule13

Member III
The current condition upon hooking up my batteries for the first time this season.

- Hook up batteries, all is fine.
- Turn on power at the 3 way selector switch
- One of the two warning horns sounds on the Yanmar YSM8
- Confirmed the key isn't in the ignition.
- Confirmed this happens regardless of which battery is hooked up and which setting on the selector switch is chosen(1,2, both)

Thinking isn't something in the wiring or the sensor itself. Not entirely sure how to even begin troubleshooting, and would appreciate any suggestions.

Thanks,
Chris
 

Baslin

Member III
The warning buzzer is most likely from either the low oil pressure switch or the high coolant temperature switch. Most likely the low oil pressure alarm because like you said, the engine is off and therefor you have no oil pressure. These switches are basically just a ground for the warning buzzer. At least, that's how most are wired. You are probable getting 12v to the buzzer while the key is off. You might have a bad key switch or possibly a short in the wiring where you are getting power to the warning buzzer when the key is off. I would suspect that your key switch is bad.
 

csoule13

Member III
Thx. What's interesting is that when I insert the key and click it to on(but not start), what I assume is the low oil pressure alarm goes off. Which is SOP (plus it motivates you to get the engine going and stop annoying the marina). So my thinking is that it is the water temp alarm.

Going forward, I'd assume pull the panel, hope nothing self-destructs due to age, and see what's what. Tracing wires will be nearly impossible since someone wrapped the bundles of wires together with electrical tape. *sigh* I'd do a new engine install tomorrow if it wouldn't cost more than the boat is worth(full disclosure, it isn't an Ericson, but the other family boat is, and you all are awesome).
 

csoule13

Member III
To keep the story going in case anyone else runs into this issue in the future.

Poked behind the engine panel and it's....pretty good. A little crusty, but neatly wired and connections shrink wrapped. I was a bit stunned. Decided to try starting the engine. Power on at the selector knob brought the alarms on, but starting the engine quieted everything. Which leads me to believe the unit the key goes into is the culprit - it is acting like the key is in the on position.

I was quite pleased with myself for this bit of troubleshooting, right until I noticed the wispy smoke coming up from below deck. But that wasn't going to be debugged after a full day at the office.
 
L

Leslie Newman

Guest
I would use a multimeter and check the ignition switch terminals to see if the +12v was hot all the time, no matter the key position. Sounds like yes the ignition switch is faulty. I often use a very long wire clipped to the ground terminal on the battery so I can clip that wire to the black lead of meter and probe around with the red lead of the meter. That way I know my negative lead of my meter is at ground and I can find where +12v shows up in reference to known good ground.
 
Top