Engine thats been sitting for 10 years 4.0

[sinkrun]

I have a 89 4.0 that been sitting inside unhetaed garage for about 10 years. The story I got when I bought it was that it was rebuilt with no more than 10k on it. 

 

Now 10 years later my MJ engine is staring to sound like a diesel MJ which it is not. Looking for a winter project I am going to pull the head and pan and check it over. Do you guys think it will be OK from sitting or should I just plan on another rebuild.

[Keyav8r]

10 years in an unheated garage. Hundreds of heating-cooling cycles and condensation. I'd bet on a rebuild.

[cruiser54]

I have a 89 4.0 that been sitting inside unhetaed garage for about 10 years. The story I got when I bought it was that it was rebuilt with no more than 10k on it. 

 

Now 10 years later my MJ engine is staring to sound like a diesel MJ which it is not. Looking for a winter project I am going to pull the head and pan and check it over. Do you guys think it will be OK from sitting or should I just plan on another rebuild.

Run it. Nothing wore out sitting still. 

[Minuit]

My engine was run to 144,868 miles then parked outside for 8 years and suddenly restarted with nothing but an oil change beforehand. Still runs good to this day. You'll be fine.

[FrankTheDog]

Just installed a 94 4.0 HO into a 99 XJ this past winter. Had 140k on it. It sat out side under a K10 truck topper on a tire for 7 years.

All we did was pull the pan and valve cover to put new gaskets on and closed it back up.

The cylinders looked clean with no rust.

Put it in and fired it up after cranking it a bit with the coil wire off. Ran mint, guy was happy.