Re: Ran Mercury 150 hp out of oil
Hey man, Well im glad to hear that the motor is still running well. However when you run a 2 stroke out of oil there isnt any lubrication, So inside the cylinder walls I would have to say yes, you have either scard the cylinder walls and or hurt the rings. Also the bearing connecting the rod to the piston maybe making noise now (the wrist-pin). the only thing I could say to fo to try and run it a little more rich when adding your oil, just to make sure that the motor has plenty of Lubricant. I have a 1976 merc 150hp and it calls for a 50:1 gas mix, I would try like a 55:1 mix. I have a question for you as well. do you know what prop size, pitch and diameter you using ?? Happy boating!!
55:1 isn't richer, it's leaner, and besides this is a VRO engine.
You can add a little oil (like 1 oz/gallon) to the main tank. I do that with an XR4 because I beat the snot out of it all the time and want it to run about 40:1 at WOT. I also use full synthetic oil.
Now for the bad news. The oil alarm should have gone off when you still had about 1/2 hour of oil in the reserve tank. If you ignored that, or ran out of oil before you made port, you should have shut down and called for a tow. You absolutely cannot run a 2 cycle engine without oil any longer than you can run a 4 cycle engine without oil. That time limit is measured in seconds.
If you ran with the alarm going, it probably had oil for the first half hour or more. Maybe you got lucky. Usually they will stick a piston within a minute or so of oillessness.
Your engine is louder because you have internal mechanical damage, or your ears just got more attentive. At this point, if you ran it out of oil, and if you continue to run it, I can almost guarantee you will grenade it in short order. If it's worth saving, now is the time to tear it down and refresh the bad parts, probably all the bearings, rings, and seals including crank sealing rings.
hope it helps
John
