Malibu stopped without oil

[evanlaczi]

Out on my 1998 Malibu response lx. Boat ran great for about two hours good oil pressure and temp. All of a sudden motor stopped and red Light came on. Saw oil in bottom of bilge. Towed back to dock. Found out oil drain plug loosed up.and poured out a lot of oil. Not sure how much came out dip stick looked dry.  What is my best course of action? Does my boat have a feature that shuts boat off when low oil? I haven’t ran boat yet.  Was gonna get new oil and run it. Then do oil change any ideas? 5.7 Chevy 350 carb motor. 

[Bozboat]

Sudden stop without oil sounds like it seized.  Will it turn over by hand or with the starter?  If you can get it to turn over then you might as well fill it with oil and see if it will run.

[Woodski]

@evanlaczi:  The procedure I would follow:  first don't simply try the starter knowing the engine stopped.  Take a large screwdriver and try to turn over the engine by hand.  Pull all the spark plugs and to access the flywheel there should be a large rubber plug on top of the bellhousing allowing access to the flywheel.  If it turns over easily then you can proceed with next steps.  I would drain the oil (whats left) and remove the oil filter (don't throw it away) to cut it apart to examine the filter material.  The filter should give you a clue as to bearing condition and what may happen even if it does still turn over.  If you can't turn it over, time to remove and rebuild/replace.  If you can turn it over time to see if there is still significant damage (probably yes).  You can fill the oil, install a new filter and give it a try.  Once it starts and is running it is key to listen carefully for any knocking noises which if present indicate a spun or damaged bearing.  Any knocking noise indicates you need to stop and repair as further damage will result if you keep running it (if a spun rod bearing as an example which is highly likely, it will allow the piston to hit the head and cause more damage).  If you simply damaged the bearings, you may get off pretty easy with a bearing and crank repair. 

[MadMan]

1 hour ago, evanlaczi said:

Out on my 1998 Malibu response lx. Boat ran great for about two hours good oil pressure and temp. All of a sudden motor stopped and red Light came on. Saw oil in bottom of bilge. Towed back to dock. Found out oil drain plug loosed up.and poured out a lot of oil. Not sure how much came out dip stick looked dry.  What is my best course of action? Does my boat have a feature that shuts boat off when low oil? I haven’t ran boat yet.  Was gonna get new oil and run it. Then do oil change any ideas? 5.7 Chevy 350 carb motor. 

No, it doesn't have an auto-shut off. 

If it were me, I'd turn the key, see if the engine turned over.  If so, add some oil to get it in the safe zone, then try and start it.

The engine suddenly stopping with the oil light on is unlikely a coincidence.  Most likely the engine is toast.

 

[evanlaczi]

Added oil started up. Oil leaking from oil sending unit. Replace whole unit? 

[tvano]

yes, if the sending unit is leaking replace it.

leak can also occur at the "T" that allows the second oil sending unit.

 

 

[MadMan]

1 hour ago, evanlaczi said:

Added oil started up. Oil leaking from oil sending unit. Replace whole unit? 

Sounds like this is the low oil pressure / fuel pump shut off, probably saved your engine.

[Bozboat]

2 hours ago, MadMan said:

Sounds like this is the low oil pressure / fuel pump shut off, probably saved your engine.

also OP should buy a lottery ticket as it appears (insert pronoun) may be very lucky

[Sixball]

If it stopped sudden it sounds more like seized. If the fuel pump shut down on the pressure sensor they don't just stop. They generally fart and stumble, backfire till all fuel is used. You might get a good idea just sticking your nose in the oil cap. It might have a death smell!  But if it even got close to seizing you could have significant damage even if it restarted. and could have a very bad experience down the road (lake). At this point its likely A rebuild. As Woodski said I would have a good look at the filter element.  Send a sample out for evaluation.    

[Rednucleus]

How much oil did you have to add to get back to proper level?

[Sixball]

What is bothering is "All of a sudden motor stopped"

[Bozboat]

53 minutes ago, Sixball said:

What is bothering is "All of a sudden motor stopped"

Seems it should be one of two things, either the oil pressure switch shut it down on low oil pressure or the motor self destructed.  Given he was able to get it running again, it did not seize.  So why did it stop running?

IDK how the oil pressure switch interacts with the fuel pump on a Carb boat.

[Sixball]

3 hours ago, Bozboat said:

Seems it should be one of two things, either the oil pressure switch shut it down on low oil pressure or the motor self destructed.  Given he was able to get it running again, it did not seize.  So why did it stop running?

IDK how the oil pressure switch interacts with the fuel pump on a Carb boat.

That is why I have concerns.  The carb boats I have been on that was triggered to shut down for oil pressure issue was not sudden! They had to run the fuel out of the bowls. The fuel pump shuts down not the ignition.  Plus if you scuff a bearing no telling what the life expectancy is. Piston wall scuffing? 

[MadMan]

Considering it was the oil pressure/fuel pump switch that was leaking, it wouldn't be much of a stretch that it could have malfunctioned with all the oil leaking through it.  It could have switched off the fuel pump while the engine still had good oil pressure.

Either way, if it were me, if it doesn't have rods knocking, I'd let 'er rip.  I sure wouldn't pull it apart looking for scuff marks. 

[Bozboat]

6 minutes ago, MadMan said:

Considering it was the oil pressure/fuel pump switch that was leaking, it wouldn't be much of a stretch that it could have malfunctioned with all the oil leaking through it.  It could have switched off the fuel pump while the engine still had good oil pressure.

Either way, if it were me, if it doesn't have rods knocking, I'd let 'er rip.  I sure wouldn't pull it apart looking for scuff marks. 

Do carb boats have electric fuel pumps?

I agree with the run it till it is really dead plan, just curious about why it would stop suddenly and then later run (even if limping)

[MadMan]

11 minutes ago, Bozboat said:

Do carb boats have electric fuel pumps?

I think they went to electric fuel pumps when GM stopped machining the mechanical fuel pump boss on the engine block (because everything GM sold had fuel injection).

[Bozboat]

16 minutes ago, MadMan said:

I think they went to electric fuel pumps when GM stopped machining the mechanical fuel pump boss on the engine block (because everything GM sold had fuel injection).

That would make sense, leak in oil pressure sender/switch killed the fuel pump power and it shut down.

[cla10beck]

If the OP's carbed engine is similar to my old 1998 sunsetter, the oil pressure switch that shuts down the fuel pump is in a different spot than the oil pressure sender for the guage and the switch for the alarm.  The oil pressure switch that cuts off power to the fuel pump is on the rear of the engine on the opposite from the distributor and shuts off power at ~5 psi.

[Woodski]

Very nice she fired back up with oil pressure, tip your hat to the shut off feature and go buy that lottery ticket.

I would recommend cutting open the oil filter after you let the engine circulate the oil just to verify all is A ok.  Sounds like you ducked that bullet.