Precisely the reason I change my own oil. But I know not everyone does or can.

Engine damage, if it exists, will vary from case to case. Neither we nor the OP can diagnose this from a keyboard. Time to get the tools out.

 

Must have been the residual 10w30 clinging on that saved it. 0w30 and it would be toast haha.

 

Sort of like an electric motor with sleeve bearings....3 drops of oil every year!

When they first started "cash-for-clunkers" some junkyards thought they could save a dollar and would poke a hole in the oil pan and wire the throttle wide open. What they found out was some engines ran for hours before seizing! The procedure that did work was to drain the oil, install the drain plug and fill the crankcase with sodium silicate which effectively destroyed the oil film.

Seriously, running without oil is not good but it is nice to know there is a very good chance that little/no damage was incurred.
I have seen agricultural irrigation pumps with Chrysler slant six engines run unattended many hours. More than once were some of them found without oil on the dipstick when checked for re-fueling.
So to the OP...get your oil loss diagnosed and corrected first then go from there. The 4.0 is a tank of an engine. My 2000 4.0 has been running on 4psi for well over 3 years.

 

I assume that reading is from the dash gauge, and while idling? It probably wouldn't last for 3 years while running at 4 psi.

 

My jeep (2004) has a dummy gauge so it reads 0 at idle. Mechanics test gauge reads 4 psi @ 650 and 20 psi @ 2500. Jeep runs like a scalded dog and is very quiet. I suspect a cam bearing. I have a standby engine ready to install when (and if) that one ever starts to make a fuss.

 

Hmmm....this explains a lot lol

 

Ok....so I'm thinking that it's safe to say all I gotta do is replace that part and crank her up....i don't have to re prime the oil pump or anything like that yea?

 

congrats you found it. Now make sure distributor or oil pump is not locked up

 

Hers what I'm thinking...

1. Put oil back into engine.

2. Prime pump and assure the sump is still operating correctly

3. Set to top dead center and correctly install new distributor

4. Run up jeep and check for knocking and correct oil pressure

Am I missing anything?

 

Inspect things to see what caused the hold down clamp to break. I have a suspicion that you did not have the oil pump drive slot lined up when you installed the pump. When you tightened the two pump mounting bolts you pushed up the distributor drive and broke the clamp. Just a logical guess.

 

No cause I took that off in order to install the pump...the distributor was the last thing I put back together...I was just figuring it's old and I might off put the screw that holds it down on a lil to tight

 

Sounds like your onto something. Let us know and good luck.

 

Happy fourth everyone! spent a few hours of my night taking off the oil pan to look under the engine for damage and I found some shimmering glitter sized metal in the left over oil in the pan as well as a milky looking substance floating in there(coolant?). Now I'm not sure bout this but my cylinder walls looked like they had some charing at the bottom of them. Any idea if that's normal or possible damage from operating without oil pump? When I run my finger over the shiny part of the wall its smooth all around except for where it's all brownish. Then it starts feeling like sand paper. Thanks y'all

 

The piston is smaller than the boar and it's the rings that make the seal, (of course). The piston "skirts" are what can make contact besides the rings. (they, of course help keep the piston from tilting on the wrist pin). There is always some shiny stuff in the pan, and the brown is just normal varnish.

I suppose the roughness where the skirt wore on the cylinder without oil IS an issue. That fit, skirt wear and cylinder taper is one of the two last things you don't really want to see in an engine, (clearanced rods being the other).

I'd run it and listen, piston slap you can hear. If it's bad, take it from there. My 02 anyway.