2008 Hunter 36 with a Yanmar 3YM30. Boat is fairly new to us, became ours late last season. Last year we paid to have the boat winterized, this year doing it ourselves. Done the same for many years with all our boats. The service person we hired last year mentioned that he got the engine winterized, but that it would not start. Came to to splash the boat this spring, it fired right up and I forgot about it. No issues at all this season, the Yanmar ran like a champ, much quieter and less vibration than our previous boat that had a Westerbeke 2B20. Now the boat is on the hard again, just hauled. Motor ran fine all season, including delivery to yard for haul. Came out a day later. Ready to winterize, all set with hoses, bucket in cockpit, pink stuff. Turn key to start, turns over but will not stay running. Let key go back to "Run" from "start", all stops. Only difference is the boat is no longer floating. Could it be a short in electrical somewhere that only pops up when boat is dry? I'm puzzled. Any ideas?
Odd Yanmar issue
- Thread starter George Braun
- Start date
Very strange. Is it a saildrive or straight shaft? If it’s a saildrive maybe there’s some kind of fuel cutoff activated automatically when the drive is not submerged?
It also begs the question how the mechanic winterized the engine last year without running it, as the usual process is to run a few gallons through. But I guess it didn’t freeze last winter so whatever was done was good enough.
It also begs the question how the mechanic winterized the engine last year without running it, as the usual process is to run a few gallons through. But I guess it didn’t freeze last winter so whatever was done was good enough.
Fuel is 3/4 full, and valve is still open. Mechanic last year just leaned on the starter until had flow through, doesn't take long. it's a straight shaft. My random thought is that electrical conductive changed with boat out of water and has affected something. All I can think of, thus the question to the group
not in gear, batteries all good with full charge. I've never heard of a cutoff that prevents an engine start on the hard, but the boat is still new to us. All I know for sure is that 24 hours prior to haul, we left our slip under power as normal, and the only thing that happened was the boat was towed to the slings and hauled. I think I am really reaching to suspect an electrical conductivity issue between wet and dry, but it's all I can come up with. Stranger things have happened.
As john says, the neutral safety switch and the electric engine stop system (relay, solenoid and wiring) would be prime suspects ..
I am 95%+ sure the engine is in neutral, I will need to study up on both the neutral safety and engine stop wiring, as all we've had in the past is a engine stop pull mechanically connected, as most all 70's vintage boats were.
Sounds more like a fuel problem. Might be a longshot, but what if the hull is flexing due to being blocked on land and is pinching a fuel line?? bypass the whole fuel line/tank setup with a small fuel can, a primer ball and attach directly to engine .
I've heard that, I'm just puzzled due to the only change being in the water and out.
If the engine turns over but will not start, it's not an electrical issue.
Compression, Fuel and air. One of these is missing.
Compression, Fuel and air. One of these is missing.
The engine stop relay and solenoid are powered through those same crappy multi connectors that are known to be a problem.. Agan, I'd be looking really closely at the neutral safety switch adjustment; if it is set too loosely, changes in the hull may be allowing it to open even with the selector in neutral. There is a great wiring diagram for that engine on this site.. click on "Owner Resources" then "General Downloads" then scroll down to Yanmar 3YM30 Service manual..
Please clarify, you say it "will not stay running". Do you mean you only detect sound of the starter, or is there some sound of running (cylinder firing) until you let the key go?
Ok, issue identified but not completely resolved. To summarize - Boat is on the hard, has fuel, engine turns over but doesn't catch and run. Wanted to run to winterize. Ran fine all season, no issues. I've discovered that the issue is the fire suppression system. Halon or it's more recent equivalent. On the engine panel there is a switch with "normal" and "override" positions. Automatic system that is triggered by excessive heat in the engine compartment. So far as I know and can remember, while in the water this year the switch has always been in the "normal" position. According to the boat owner's manual, once system has be triggered, the "override" position is intended to allow the engine to run after a triggering event. There is also an idiot light labeled "discharge".
This past weekend when I turned on the boat with the switch in "normal" position the engine again will not start. When I set in "override", the "discharge" light comes on, and the engine starts right up. Only thing different is the boat is on the hard. System bottle gauge reads within normal range of pressure, hasn't been discharged. There is essentially nothing in the main boat documentation about the fire suppression system.
1 - anyone have a source of information on this system?
2 - any thoughts on grounding, conductivity, wiring shorts, or the like that would be triggered by the boat being dry?
I'm not sure I really care about a fire suppression system, have had diesel engine sailboats for over 30 years without ever having a fire or related issue, so if it's too intricate an issue may just leave the switch in override and go on with life.
This past weekend when I turned on the boat with the switch in "normal" position the engine again will not start. When I set in "override", the "discharge" light comes on, and the engine starts right up. Only thing different is the boat is on the hard. System bottle gauge reads within normal range of pressure, hasn't been discharged. There is essentially nothing in the main boat documentation about the fire suppression system.
1 - anyone have a source of information on this system?
2 - any thoughts on grounding, conductivity, wiring shorts, or the like that would be triggered by the boat being dry?
I'm not sure I really care about a fire suppression system, have had diesel engine sailboats for over 30 years without ever having a fire or related issue, so if it's too intricate an issue may just leave the switch in override and go on with life.