So sometimes, no matter who it is, we goof up and make mistakes. Today I started the motor with no oil in it, or at most just just what was left on the surfaces of the internals and in the lines and coolers. Today was oil change day so i went ahead and drained the oil and replaced the drain plug. I also decided to replace a bad EGT sensor since the car was jacked up. I had to leave the car to pick up the sensor and the actual installation took about 2hrs. By this time I did not remember that I had not put in the new oil as yet. I went ahead started the motor and it immediately revved to about 5000rpm. I was watching the oil pressure gauge all this time and it did not budge. Instantly I remembered I did not add the oil and shut it down.

The motor ran for 6seconds peaking at about 5000rpm.

I since filled it with oil and started it(initally turning off fuel pumps while cranking for about 10secs to prime it with oil). There were no abnormal sounds and it runs fine.

Is it likely I did any damage? Has this ever happened to anyone else?

 

It's fine.

 

I had rebuilt an engine before, Land Rover V8. When I started it up for the first time, obviously there was no oil in the circuit or anywhere else other than the oil pan.

It made horrible "something isn't right" noise for 4 seconds or so then as the oil made into places the noise went away.

I have put on about 50k miles since without any problem.

Now having said that, every engine is different due to previous history let alone difference in design.

You have worn the housing and seals down in some amount very fast in a very short period of time. Seems like nothing broke according to your description.

Say it did damage the engine, worrying about does not change anything.

If not already, I would put on some magnet on the oil filter to keep the microscopic shaving floating around in the oil damaging the internals. I would not drain it right away because you need to filter out these shavings with this oil in the crank case. But definitely would shorten OCI this time and the next and will use good oil filter or oversized filter big magnet on the filter.

 

6 seconds and there was previously oil in the engine? You're fine.

 

Rpm is one thing. Load is another. You will be fine as long as it had oil in it previously.

Anyone remember the oil commercials where they would put a brick on the gas and then drain the oil. Even the supposedly inferior oil lasted quite a while within failure just from the residual.

 

I did a stupid thing the other day...
Changed my oil & filter, started my car and all my new oil spewed out of the oil filter pedestal..

Thought oh crap the oil filter isnt tight enough (id already done that one a few years back lol)..so I cleaned everything up, and tightened it more with an oil filter strap wrench...

Started car again, oil spewed out again...ugh...what a mess lol..

Removed oil filter, and found the rubber seal from the old oil filter had come off and was still on the oil filter pedestal..so I had two seals on there hence the leak...

 

That was funny . Same thing happened to me about 15years ago on my turbo prelude. I thought I busted the damn filter from high oil presssure since I just modded the oil pump for higher pressure.....Seriously

 

I did that same thing my first month working at a shop while the customer was out front waiting... Oil gaskets often cook themselves to the pedestal when the last guy to change the oil was a jiffy luber who cranks them on as tight as they can with a filter wrench.

 

If the motor didn't seize, it's fine. However, it's not worth worrying about unless you feel like taking the motor apart to check.

 

Its fine

Forgot to prime my system after installing oil coolers on the 20b. Started it up to 2k rpm and O **** no oil pressure, cut the fuel instantly. Ran for a total of 5-8 seconds.

Primed the system, pressure popped right up. All is good.

 

loose oil filter, drove down the street to the gas station, puked most of the oil out (only a small amount at the bottom of the pan. engine was fine.

 

Depending on your oil coolers (stock or after market) you might have had a quart of old oil from the lines and coolers

 

There is a sign on my garage wall that says 'No Oil!' in a very large font.
That sign gets taped to my steering wheel when the oil is drained and any work is done.

 

.

 

ditto

except i completely forgot to put my oil filter on. this was on my old na years ago. needless to say.. it was a mess. lol

 

Ran my BMW M5 V8 (E39) with no oil in the sump for about 2 miles or so. Sump had a hole, middle of nowhere.

Got to civilisation, filled it back up with oil and patched the sump. Engine ran fine for another 3 or 4 years til the car got sold.

You'll be okay. At worst, you've wiped some white metal material off the shaft bearings and shortened their service life by a very small amount. It should be fine.

 

I agree, you should be fine.

Rotaries are much kinder to bearings than piston engines. If the engine was bone dry from sitting for 10 years or something I would be worried, but it had run recently and still had a good amount of oil in the system.

I had an oil cooler line blow on my old FC, it ran maybe 10 seconds after that, I immediately shut down and pulled off the road. Fixed it up. A while later I went through the engine (popped apex seal) and there was no significant bearing wear or damage. This was also driving with load which is a factor as well.

Dale

 

I've got one of those, in addition I have a sign I put on top of the engine that says DRAIN PLUG, I couldn't count the number if times I've remove the drain plug come back 20 minutes later and basically pour a quart of new oil into the oil drain pan.