SummertimeBlue
Newbie
I have an intermittent problem starting the 370 HP Yanmar engine on my 2006 Mainship 34 Trawler. This is the 4th year we've owned the boat, and this year is the first year this has occurred.
1. I switch the "Eng 1" switch on (is a single engine boat).
2. I press the button on the electronic engine control - orange indicator is on.
3. I turn on the engine key switch - immediately the "low oil pressure" alarm sounds - as usual.
4. And I press the start switch - nothing. No mechanical noise, no starter grinding, nothing.
My question is what signals would interrupt engine starting. For example, the fire suppression alarm would I believe shut off the engine. Are there other alarm conditions that would prevent starting the engine. By the way, once started the engine has run fine.
At first I thought it might be a "low voltage" interlock preventing starting the engine - since it seemed to be an issue if I disconnected the AC power from the dock prior to turning on the electronics and then starting up the engine.
This last time, after refueling at the fuel dock, the engine was off for 15 to 30 minutes (all electronics on) and wouldn't start. I finally got it to start after charging the batteries with the generator for 30 minutes. But the battery voltage was not low - maybe 12.5V on the small panel meter.
Also, the electronic engine controller appeared to be working - I could hear it shift the transmission for example. So I don't think that was blocking startup.
The yard load tested the batteries - all tested ok. The mechanic couldn't reproduce the problem - engine started fine.
Yesterday I went down to boat figuring I could reproduce the problem. Turned off the battery charger, put a DC load on the batteries for a while, tried turning the engine on and it started up. Kept load on the batteries for a while still started up every time.
Only difference was the last couple of days the outside temp drop down 20 degrees.
And one final piece of evidence - the "low oil pressure" alarm is normally silenced with the "off" position of the engine start switch at the helm. But when this problem occurs and the engine won't start - the alarm buzzer cannot be silenced.
Any ideas?
1. I switch the "Eng 1" switch on (is a single engine boat).
2. I press the button on the electronic engine control - orange indicator is on.
3. I turn on the engine key switch - immediately the "low oil pressure" alarm sounds - as usual.
4. And I press the start switch - nothing. No mechanical noise, no starter grinding, nothing.
My question is what signals would interrupt engine starting. For example, the fire suppression alarm would I believe shut off the engine. Are there other alarm conditions that would prevent starting the engine. By the way, once started the engine has run fine.
At first I thought it might be a "low voltage" interlock preventing starting the engine - since it seemed to be an issue if I disconnected the AC power from the dock prior to turning on the electronics and then starting up the engine.
This last time, after refueling at the fuel dock, the engine was off for 15 to 30 minutes (all electronics on) and wouldn't start. I finally got it to start after charging the batteries with the generator for 30 minutes. But the battery voltage was not low - maybe 12.5V on the small panel meter.
Also, the electronic engine controller appeared to be working - I could hear it shift the transmission for example. So I don't think that was blocking startup.
The yard load tested the batteries - all tested ok. The mechanic couldn't reproduce the problem - engine started fine.
Yesterday I went down to boat figuring I could reproduce the problem. Turned off the battery charger, put a DC load on the batteries for a while, tried turning the engine on and it started up. Kept load on the batteries for a while still started up every time.
Only difference was the last couple of days the outside temp drop down 20 degrees.
And one final piece of evidence - the "low oil pressure" alarm is normally silenced with the "off" position of the engine start switch at the helm. But when this problem occurs and the engine won't start - the alarm buzzer cannot be silenced.
Any ideas?
Last edited: