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I'm considering replacing my 4.2 with another remanufactured 4.2 before too long. I'm going to ask a co-worker to help me (he's a former mechanic, and has air tools, a hoise, and so forth).


Before I bring it up and ask him, how long does it take to replace an engine if you've got everything ready to go? It's a 4.2, not computer controlled, so there aren't many electronics to mess with.

Gracias,
Tim
A day at most. Basically it is a matter of draining coolant, pulling tranny/t-case, unbolting all the hoses, pulling old engine, swapping accessories (much easier while engine is out), and going in reverse. If you have a manual it is a great time to also replace the clutch/throw-out since you have it all apart already.

If you are going to be swapping it out anyways why not go with an AMC V8?
A day at most. Basically it is a matter of draining coolant, pulling tranny/t-case, unbolting all the hoses, pulling old engine, swapping accessories (much easier while engine is out), and going in reverse. If you have a manual it is a great time to also replace the clutch/throw-out since you have it all apart already.

If you are going to be swapping it out anyways why not go with an AMC V8?

Money. Can't afford a new tranny or t-case.
I can't see it taking more than a Saturday of dedicated work.

However, I'd also recommend that if you've got a manual trans, that you get the flywheel resurfaced or replaced and install a new clutch kit. You don't want to have to drop the trans/tcase in three months....
It all depends how good you are and what you run into.To be safe I would plan on at least a full weekend.
A day at most. Basically it is a matter of draining coolant, pulling tranny/t-case, unbolting all the hoses, pulling old engine, swapping accessories (much easier while engine is out), and going in reverse. If you have a manual it is a great time to also replace the clutch/throw-out since you have it all apart already.

If you are going to be swapping it out anyways why not go with an AMC V8?

Why would you pull the tranny and t-case? Makes no sense to me for a engine swap.

To the OP, pull the front clip off as one unit, 10, 12 bolts I think, 8 on firewall,1 for front mount and 3 for the braces, 2 grill rods, undo wiring for lights and ECM, radiator hoses, overflow tank, windshield washer tank, battery connections, solenoid, leave the rad in the grill and just pull it off as 1unit,

Undo all wiring on motor from harness, take off fuel lines, take PS off, take off exhaust, set chain on motor, hoist it, undo all bellhousing bolts and undo motor mounts.

It shouldn't take more than a day to do this, I have done a couple in less than 6 hours. You can even making it faster by getting it ready to swap with some help.

Reverse on install. Ditto on a clutch.
Why would you pull the tranny and t-case? Makes no sense to me for a engine swap.

Never had any luck getting the engine to mate up with the input shaft of the tranny. Realatively easy vise versa.
I guess if you are really lucky with engine hoist placement and have an extra set of hands to help maneuver it could be done.