What do you think I did?

I've felt too stupid and embarrassed to ask this...
I got that cobbled up 4000/4400/3500 running about a year and a half ago.
Made the gasser a diesel. It ran great. Put about 20 hours on it. Just tooling around. Never finished the tractor. It needs tires, 3 point not working right, wiring etc.
Had to bring it up north in May a year ago to make room for the new garage here at home. Parked it in a shed.
It just had water in the radiator so I drained it when I put it away.
Not worried about having froze it.
Out of sight, out of mind. I got on to other projects.
Fast forward to June of this year I thought I would see if it would start. Put a battery in it and it fired up almost instantly.
Sweet!
I let it idle for 4 or 5 minutes. Oil pressure on a gauge read ~60? psi - no cluster yet. It started smoking black. Backfired when I tried to rev it a little.
Then I realized there was NO coolant in it. Ouch! I shut it off and have been sick when I think about it.
Going back up north this weekend. Will put 50/50 in it and see if it will start.
What happens if you take a diesel and run it for 5 minutes at low idle with NO coolant.
It's still parent bore - no sleeves.
I'm hoping worst case is I'll need a set of rings, right?
What do you guys think - about the engine mind you - not the part about being dumb?
Thanks

I dunno, but I'm going to bet in that amount of time, at an idle, it did not get hot enough. Could be wrong, but can you see the block getting dangerously hot at an idle in that short of time?

Black says too much fuel. Would not think it would be black from heat.... Diesels run cool anyway. Maybe no damage?? Let us know what happens..

Did it once on 4500 I have. Block had water proably up to waterpump level. Relized it killed and left till next day, Doesn't seem to have hurt yet.

More than likely it will be fine. I doubt very much if idling a diesel 5 minutes will hurt very much of anything. Good luck!!!

I don't think that you can get a diesel up to operating temp in 5 minutes unless you put a pretty good load on it after two minutes.

Well... don't make a habit of it. 😛
I agree with the others. I don't think you hurt it.
About 20 years ago, I bought a Ford 620 combine that had a 256 gas engine. It was stored with the radiator drained. Took coolant with me when we went to get it... fresh battery and gas... fired up and away we went. My cousin was driving it for me while I followed in my pickup. A couple miles down the road, I noticed the drive tire was wet. The radiator drain had vibrated open. By the time I got around him and got him stopped, it was pretty much empty, and steaming. I guarantee you that, at near full throttle and pulling the combine down the road, it was way hotter than your engine. Let it cool, refilled it, and fired it back up. Never an issue from it.

We run training aid engines all the time at our shop for sometimes 10-15 minutes with no water. Tear them down the next time and everything looks fine. Diesels don't generate enough waste heat under no load for it to be much of a concern.

I once took a 15 liter Cat engine and let it run outside on a freezing morning. Could not get the temp over 160 no matter how long it ran. And, the thermostat was closed and the fan was off. Ford diesel pickups can be ordered with an electric heater option because it takes so long for diesels to warm up.

Put water (err, I mean, coolant) in it and don't look back.

The smoking and backfire is a bit troubling. I assume by "backfire" you mean the exhaust popped, which would mean lots of unburned fuel getting into the exhaust.

As everyone else said, fill the coolant, start it up and see what happens. The smoke may have been unrelated to running it without coolant.

That's not near enough time to hurt anything but your feelings.

I came up this morning.
Mowed for a few hours with the little tractor then put 50/50 in the radiator and a battery in it.
It must still have rings in it as I doubt it turned over a full revolution and fired right up. I backed it out of the garage it's in and let it idle for about 15 minutes. Smoke cleared up and it just idled real nice. I wanted to take it for a spin but one of the fronts is flat.
I should have driven up here a couple of months ago and done this as I've worried about it a lot since it happened.
Time will tell but I might not have hurt it.
Makes me want to finish it now but that will have to wait. I think it would eat the 3000's lunch if I hooked it to the bush hog.
Thanks to all. You helped put my mind at ease.

Good to hear it seems to be OK.

I know the feeling, having somehow filled my yellow diesel can with gasoline which ended up in the fuel tank of the 4630. Did not run right soon after. No damage done, but was worried until one of the dealers service guys drained out the fuel and changed the filters.