Having a fair amount of knocking. The head is also in need of a rebuild. Figuring when i got the head off I could drop the pan and replace the crank and rod bearing as well as rings. Is that feasible?

 

Yes an "in frame" rebuild is possible thanks to the inline nature of the engine. Need to remove the hood and front axle to get it out of the way to give room to work.

 

You will technically need to pull the trans out too so that you can lower the crank enough to get the main bearings out. I mean it is possible to do it with the trans still in but there is a lot greater of a chance of hurting something. Plus, if its knocking, there is a good chance that the crank will need to be "turned". Possible? Yes. Best choice? No.

 

I have replaced pistons and connecting rod bearings with the engine in place. This was for a cracked piston skirt. AS 5-speed said, you would need to drop the trans to get the crank out. You could plastiguage it first to check. I did not do that since I needed to get it back on the road. I figured I'd have taken it off the road to rebuild the motor all the way, but the work I did was ~4 years and 20k miles ago. Oil pressure was always good and remains good.

 

If you have the head and trans off you might aswell just pull the engine. I did a ton of work to 2 different Small Block Chevys in 3 different trucks. When it came time for round 3 later on, I just pulled the engine and was so glad I did. It make everything so much easier

 

My mate, over 60yrs a pro mechanic, he pulled an XJ engine to replace a damaged piston (+ hone, new pistons, rings and bearings).

Got it for nothing, as client declined to proceed, and aimed at a quick resale. He knows every shortcut.

Stated its easier to pull an XJ engine, did have helpers though

 

I have done a partial rebuild on a 2.5l in the vehicle - pulled head replaced bad piston and honed. For what you're describing, I'd pull the engine. By the time you've got all head off, it's not much more work to unbolt the engine mount and tranny. Have you determined what's knocking? It would suck to do a rebuild and discover it's just the flywheel bolts backing out.

 

X2 on this. Definitely check and do a good double check. If the bolts are tight look and pry on the flexplate really good and look for cracks. Ushally really fine cracks. I had to spray mine with break fluid to clean it so i could see anything. Let the fluid dry up and when i went back and pried on the flexplate you could see wet fluid seep out from the cracks. Still a ****ty job to do as you must still pull the tranny to replace it but a lot less stress and bs and way cheaper then rebuilding your engine inframe. If the engine does need rebuilt pull it out, you will be thankful for it in the end