Yanmar 2gm engine died

Leeward Rail · Sunday at 9:11 AM

Did you check the oil level before you restarted the engine and motored back to the marina ?

When that light goes on it means the oil pressure is very low. Depending on the oil pressure sensor, It's often an "Oh Crap" light. Not a "Oil pressure seems kinda low" light.
Even if they light wasn't on when you slowly motored back, it can be low enough to cause engine damage.

Go check the oil level. When was it last changed ? When was the oil filter changed ?

Fwiw: you usually never need to use max throttle on a sailboat. Once the boat hits hull speed it's a waste of fuel because it won't go any faster.

RitSim · Sunday at 9:29 AM

Not an expert on this engine but here is what i would consider
Assuming pressure switch is correct, then
1. Oil level is low or wrong viscosity
I would change oil and filter. Cut open filter and hope that there is no metal filings inside - this would be a big deal.
After oil change, does engine operate at normal throttle?
If engine operates better after oil change - watch for thinning oil indicating fuel leakage into crankcase from worn rings or a problem with high pressure pump

2. oil pump is worn, or
You may have to add a gage to get an idea of true oil pressure. Any relationship to engine speed that gives you any clues?
If this looks like a good direction, you may consider pulling the valve cover to verify that oil seems circulating to the top of the engine
Or consider dropping the oil pan and installing a new oil pump.

3. oil usage at bearings is more than it should be by bearing wear or oil blockage.
If the pump is not the issue, then, unfortunately, either you have bearing wear or blocked/restricted oil passage

4. Either oil flow is restricted at pump suction, or restrictions at oil passages. Some people flush the engine with chemicals or adding diesel fuel. Never tried it and there are plenty of comments on both sides of this issue.

Good luck

Ralph Johnstone · Sunday at 10:28 AM

3GGG said:
Where should I look first?

Here's a good place to start :

It's quite likely you're engine has seen some major damage after a stunt like that.

Did it ever occur to you "There may be a problem with the oil level" or do you not know how to check your oil level ?

Best of luck with this. You're going to need it.

kloudie1 · Sunday at 10:30 AM

Same as above.. the switch turns the light on at 1-4 psi, .. They do go bad occasionally.. Additionally, there is an oil pressure control valve in the middle of the oil filter boss on the engine.. sometimes a piece of debris can lodge in the little ball and stick the controller open resulting in low oil pressure.. If the light went out when you lowered the throttle, then it is most likely a restricted oil pickup or a really dirty oi filter.. If the light stayed on at idle, then there is a more expensive problem..
Note that the light comes on when the switch connects the connected wire to ground.. if that connection has come off the switch and is touching a ground or if the wire insulation has chafed through and connected to ground, the light will go on..

jviss · Sunday at 1:06 PM

3GGG said:
Took my Hunter 285 out for the first time last night.

Ran fine for several miles. I pushed the throttle to max and the oil alert came on. I throttled back to idel and the engine died. It started back up and I idled back to the marina.

Where should I look first?

Insufficient data.

Did the oil alert stay on when you restarted?

Tally Ho · Sunday at 1:18 PM

Are you sure it was oil pressure and not overheating light?

The day I took my O’Day 322 with the same engine, and started to motor across Lake Michigan in a big headwind and chop, my idiot alarm went off. The engine control panel is mounted very low in the cockpit and seeing the row of idiot lights is almost impossible.

In my case, I reduced throttle and made contingency plans if the engine seized (I could not tell what light was one). While we were discussing plans, the alarm stopped. We nursed it to the next marina and inspected the engine. Turned out the fluid in the heat exchanger was very low, and pushing the engine hard through the chop caused it to over heat.

Just asking to verify that you know for sure that it was the oil pressure alarm.

Greg

smokey73 · Sunday at 1:27 PM

It is the "throttled back to idle" and it died that has me a little concerned along with the other alarm issue. First question, does it normally die when you throttle back to idle? If so, that could be the problem with regard to the engine stopping. There is no "low oil pressure engine shutdown" on these engines so a true very low oil pressure situation (0 to 4 psig) can and probably will damage the engine and I would NEVER advise operating an engine with the low oil pressure warning alarm/light sounding.

dlochner · Sunday at 1:58 PM

kloudie1 said:
Same as above.. the switch turns the light on at 1-4 psi, .. They do go bad occasionally.. Additionally, there is an oil pressure control valve in the middle of the oil filter boss on the engine.. sometimes a piece of debris can lodge in the little ball and stick the controller open resulting in low oil pressure.. If the light went out when you lowered the throttle, then it is most likely a restricted oil pickup or a really dirty oi filter.. If the light stayed on at idle, then there is a more expensive problem..
Note that the light comes on when the switch connects the connected wire to ground.. if that connection has come off the switch and is touching a ground or if the wire insulation has chafed through and connected to ground, the light will go on..

Yes the oil pressure switch can go bad and can leak a lot. Been there, done that, have the bills to prove it.

Check your bilge to see where the engine oil has gone.

jviss · Sunday at 2:06 PM

How many hours on the engine?
Have you checked the oil level yet?

smokey73 · Sunday at 5:04 PM

If your idle is set right and the engine is running correctly it should not die at idle, even in gear.

It is a good practice to check the oil level each time before you start the engine the first time in a day and to note the level, at least in your mind if not in the log. If you see it going down day to day then something is probably wrong, either a leak or burning. Of course adding a little oil every 50 to 100 hours is not out of the question but if you have to do it every day then I'd be trying to find out why I am using/leaking oil. Even if you checked the oil "a week ago" and did not run the engine, checking the oil level before you start should be part of your "underway checklist." If you don't have an Underway checklist or routine, you should develop one.

dlochner · Sunday at 6:05 PM

With the answer you have given, the first suspect is the oil pressure switch failed. Once you find it, the replacement is easy and not all that expensive, probably well under $100.

Ralph Johnstone · Sunday at 8:34 PM

You have been asked repeatedly for the oil level after the alarm incident and no reply.

Is this on a need to know only basis ?

higgs · Sunday at 9:04 PM

Don't assume the oil light and the engine dyeing are related. Running any engine at full throttle puts a strain on it. Perhaps your engine is a little tired and under stress has trouble keeping pressure up. In my experience, diesels seem to like to run around 2000 rpm.

Leeward Rail · Sunday at 9:56 PM

3GGG said:
Checked oil level a week before and it was fine.

"The wing was fine a minute ago... until it fell off and the plane crashed"

I don't mean that as snark. It's just a way to show that because something was fine.. even 10 minutes ago, doesn't mean that it hasn't changed. Never assume a new part hasn't failed. Never assume a hose or wire is still connected.

The immediate question would have been.... "Why did the oil light go on ?What's the oil level now ? Has it changed from a week before ? If it's safe to do so, I should check it before I restart the engine"

Did the motor stop as soon as the oil light went on ?
There is a chance your engine has the oil pressure switch wired so that it kills the fuel flow if the oil pressure drops too low. This is designed to protect the engine.

Check the oil level
Check oil condition
Check the pressure switch wiring
Test the pressure switch.