I have here a 2004 Jeep Wrangler, 2.4 Chrysler engine, In-line 4. Not mine, trying to assist a neighbor.
They (with almost no mechanical knowledge) determined there was a “stuck valve”. I didn’t agree, but that’s not the point. A “mechanic” friend pointed them in that direction. I’m providing free support when asked, and only when asked. They ordered a new head from RockAuto. head arrived, proceeded to rip it apart. Now they’re getting ready to put it all back together, and I was advising them on cleaning the tops of the cylinder wall, pistons and to prepare the block for the new head.
As we turned it over - no head - it binds just as it’s coming to TDC. You can pull through it without too much trouble, but it’s far from as smooth as it should be - there’s a definite stop you can feel. There’s nothing left on the crank but the transmission (still binds with the clutch in) and the oil pump.
Have inspected the oil pan - no damage. Drained the oil and filter, still binding. The only component we haven’t removed is the starter. It wasn’t vibrating excessively, so unless the flywheel is bent, the starter shouldn’t be in the way, and there’s no metal - to - metal sound that we can hear.
So unless there’s something wrong with the crank, I’m kind of at a loss as to what it could be.
Our next step is to drop the pan and inspect the bottom of the cylinder walls. I don’t see how the bottom of cyl 2/3 could be causing it, but I’ve seen stranger things.
Thanks a bunch…