Effects of no oil?

[fishmen111]

I know there are a lot of variables, but how long does it take to destroy a 2-stroke with no oil? Minutes? An hour? I hear of blown late model, high hp powerheads around here all the time usually on large bass boats. Many are covered under warranty and you hear quite often that it was lack of oil. Would the rings lock up first or bearings sieze and toss a rod? Just curious.

 

[Dhadley]

Re: Effects of no oil?

How long with no oil? It depends on what rpm you're talking about. Most of what you hear is not oil related - regardless of what they say.

 

[Robj]

Re: Effects of no oil?

You could run longer at idle without oil than you can at 3/4 throttle. So it depends what the engine was doing before it ran out of oil. It idle there is not as much heat as there is when running at full throttle.

Have a great day,

Rob.

 

[F_R]

Re: Effects of no oil?

How long with no oil? It depends on what rpm you're talking about. Most of what you hear is not oil related - regardless of what they say.

I agree. I have worked on thousands of motors and have rarely seen one that was ran without any oil whatsoever. And one of those, I did myself. (Oops). That one took about a minute and a half before the piston siezed. And it took me about 15 minutes to get a new piston in it before the boss got back from town.

 

[22ISLANDER]

Re: Effects of no oil?

In my old (very old) dirtbike days, we used to shave a mothball into the gas tank, and not premix the oil in an important race, usually the last race of the day that would pay off alot more than the engine that was about to be destroyed. If you could get 21 minutes out of a 20 minute enduro, you won. But engines were alot cheaper to replace back then, and there was nothing left of them to rebuild, other than salvaging things like carbs and screws.

On a marine engine, if you run it out of oil and it does not fail, hold onto your wallet, because it's gonna fail, and it will be a catastrophic failure.

Rings, pistons, bearings, and finally the engine block..poof...all gone.

 

[gnrboyd]

Re: Effects of no oil?

Back when I was about 18, I pulled my step dads boat to the lake by myself. It was a 1957 Evinrude 7.5 hsp on an aluminum flat bottom boat. It needed gas in the tank. My step dad and I had some miscommunication about the oil. I thought he said he already put it in. He said told me not to forget to put the oil in. Anyway, you know what happened. I didn't add any oil (25:1 as I recall) and less than 5 minutes from the ramp......kerthunk.... Some or most of the parts were NLA so we never repaired it. (That was the early 80s and no internet...we just called the local shops and had no luck finding parts.)