I got a jeep with what was thought to be a bad rod bearing.

it barely had enough power to move its self... 10 feet at most with a lot of work.

Motors out and the flex plate is TRASHED

now, usually a bad flexplate is just knocking until it is under load. This incident it was knocking no matter what.





Is my motor still good? thoughts and opinions

 

I have no idea what year the Jeep is or if it's a 4.0 or not, but...I don't think anyone here has big enough nads to tell you that motor is okay to use as-is.

You might want to check the connecting rod bearing clearances with Plastigage before using it.

Edit: What does this mean... "it barely had enough power to move its self... 10 feet at most with a lot of work." ?

 

When a motor is knocking, it is usually still drivable. In this case, it would idle fine, but once you where in gear it would stall.

 

If you think you have a bad rod bearing, driving it may make the difference between a crank that can be machined and re-used and a crank that has to be scrapped.