Engine Ran With No Oil

[humbled1]

Today I did the unthinkable. After draining the oil out of my 5.0 Mercruiser and replacing the filter. I got distracted and forgot to replace the oil. Yes, you read it correctly. I started engine up to fog it, It ran maybe for one minute max w/o oil before it shut down via fog oil. After collecting myself, I refilled the engine oil cranked engine with starter for about 45 seconds w/o coil wire attached. I re attached coil wire and then it started and oil pressure went straight to normal. I never heard any tapping sounds or anything unusual at any time. What kind of damage did I do? What can expect now?

 

[mthieme]

Re: Engine Ran With No Oil

Best case is that the bearing surfaces had enough of a coat of oil to handle it and you're okay. No noises is a good sign so the the lifters didn't go flat on ya.
Their is a good chance that you didn't anything serious.

 

[humbled1]

Re: Engine Ran With No Oil

Thanks. I was spraying fogging oil when I realized that I had forgot. There were no strange or unusual sounds a that time. Anyone else want to weigh in? Just give it to me straight :redface:

 

[Don S]

Re: Engine Ran With No Oil

Put some oil in it and start it up and see what happens. As mentioned, if the lifters weren't making noise, there was still some oil and oil pressure there.

 

[humbled1]

Re: Engine Ran With No Oil

Put some oil in it and start it up and see what happens. As mentioned, if the lifters weren't making noise, there was still some oil and oil pressure there.

Thanks Don. I was hoping you read my post. I filled with oil right away and started it up. O/P went quickly to where is normally on O/P gauge. It was running at no higher than an idle when I realized what happened. :redface:

 

[chiefalen]

Re: Engine Ran With No Oil

Don't beat yourself up over this. Probably nothing happened. You have good oil pressure, thank g-d, would be the first sign of bad things.

You were fogging you say had oil going in that way.

Do a compression check.

Or a vacuum test, Is better.

Heres the link.

It will give you piece of mind. Post the result.

http://www.secondchancegarage.com/public/186.cfm

 

[humbled1]

Re: Engine Ran With No Oil

Not sure where to hook up vacuum gauge on Mercruiser. I mean, I know how to do it but there no place to hook it up, as I remember

 

[Don S]

Re: Engine Ran With No Oil

Neither a vacuum test nor a compression test is going to tell you if the rod, main, or cam bearings are going out because of no oil.
I doubt a minute of running at idle while fogging will do anything to the cylinders.

 

[scipper77]

Re: Engine Ran With No Oil

when you start a cold engine the oil is basically in the pan. Because you never put any load (at idle) on the engine you likely didn't do much worse than starting when cold. the oil system is designed to lubricate under EXTREME loading of an engine. If the engine got hot then you might have a risk of damage as the thin layer of oil coating things couldn't stand up to the heat. other than that you should be fine.

 

[humbled1]

Re: Engine Ran With No Oil

Neither a vacuum test nor a compression test is going to tell you if the rod, main, or cam bearings are going out because of no oil.
I doubt a minute of running at idle while fogging will do anything to the cylinders.

OK. Apart from monitoring O/P is there anything else to look for or do?

 

[chiefalen]

Re: Engine Ran With No Oil

I was just trying to give you some piece of mind. Nothing happened.

In my own inexpert opinion.

Sleep well.

 

[humbled1]

Re: Engine Ran With No Oil

It would seem that something must have happened inside. Rod bearings, cam bearings and main bearings.

BTW I do appreciate your exhortation chiefalan. Thanks.

 

[chiefalen]

Re: Engine Ran With No Oil

Nope nothing, was already lubed, takes about 30-60 seconds for oil in the pan to get pumped up to the lifters, drain back down and get to the main bearings,crank and so forth.

Every time you start a car, boat, lawnmower, there is a tiny bit of wear.

But the lube is on the moving parts.

If this was a healthy motor before this mishap, then it's still a healthy motor now.

Prognosis is the motor will live.

Take 2 aspirins and call me in the morning.

 

[humbled1]

Re: Engine Ran With No Oil

I am going back down to boat again later on today. I will start it up and let run to operating temp and see what happens. Although I realize that running it on hose does not simulate running at 3600 rpm for 10 miles. So i don't know how much this will reveal. I'll post my finding later on today.

I have changed oils hundreds of times in my life and never did something like this, :redface: too much on my mind regarding winterization, I guess I was not focused on the job at hand on what I was doing right then and there. Engine only has 560 hours on it and its 13 years old.

Thanks to everyone. I wonder why Bondo has not weighed in on this one?

 

[Don S]

Re: Engine Ran With No Oil

Thanks to everyone. I wonder why Bondo has not weighed in on this one?

Last I heard, his crystal ball was broken

 

[humbled1]

Re: Engine Ran With No Oil

Lol

 

[Bondo]

Re: Engine Ran With No Oil

I got distracted and forgot to replace the oil. Yes, you read it correctly. I started engine up to fog it, It ran maybe for one minute max w/o oil before it shut down via fog oil. It was running at no higher than an idle when I realized what happened.

Ayuh,....

I quite Sure that atleast Some damage occurred,... How Much will be determined in due Time....
The damage most likely will be in the Oil Pump, Main Bearings, Rod Bearings, Cam Bearings,+ possibly the Cam itself....

OK. Apart from monitoring O/P is there anything else to look for or do?

Nope,....
Well,... Maybe cross your fingers,+ some Praying might Help....

 

[Robj]

Re: Engine Ran With No Oil

How did you drain the oil? By the dipstick tube or by dropping the plug? If it was by the dipstick tube, my guess is you did not get it all out and had enough left to fill the lifters which is why there weren't clacking. If so you should be OK. If all the oil was drained, then the lifters would definitely be clacking.

Have a great day,

Rob.

 

[scipper77]

Re: Engine Ran With No Oil

How did you drain the oil? By the dipstick tube or by dropping the plug? If it was by the dipstick tube, my guess is you did not get it all out and had enough left to fill the lifters which is why there weren't clacking. If so you should be OK. If all the oil was drained, then the lifters would definitely be clacking.

Have a great day,

Rob.

I disagree, I've heard lifters in cars make noise merely because the oil was too low. Pumping through the dipstick gets more oil out than you might think.
just my opinion, not a correction.

 

[Don S]

Re: Engine Ran With No Oil

Basically, all we can give you is a WAG. (Wild Azz Guess)
The only way of knowing for sure what damage was done is to take the engine apart and inspect each piece for damage.