Any recommendations on what motor I should swap in?

joefunicello

New Member
Joined
Dec 28, 2020
Messages
1
Location
Norwalk, Connecticut
Hello,

I am new to the Jeep community and recently purchased and restored and 1987 Jeep YJ.
The rebuild is going well. But the motor and transmission are giving me problems. I am thinking of doing a motor swap. Any recommendations on which motor I should swap into it and where to find one?
F80167D0-FC98-41DD-B1DD-04E6AA38E584.jpeg

51A6B647-B806-4849-B382-E8E1C64B78C4.jpeg
0E61A5C9-3758-4168-A042-C07D78172271.jpeg


9230E129-A9BD-4849-A46A-11B3ACF07A5F.jpeg
 
I'll be curious to see what others post here. I am not new to Jeeps but haven't had one in awhile. Just acquired an '89 2.5 with 238k on the clock. The four cylinder is such a dog that I'm curious about swapping too but don't want to swap in the 4.2 carb motor that would normally go with it. I've thought of small 4 cylinder diesel motors, the ever common (and frowned upon) LS swap or standard Chevy 350. I've heard that there are no swaps that are just simple drop in, even the 4.2 to the 4.0 can be a PITA what with wiring, motor mounts, etc. so it'll be interesting to read what others have done or read.

Good luck on the Jeep ownership, they are fun and frustrating all at once!
 
Whats wrong with the idea if a complete tear down and rebuild of what you already have?

Rebuilding the factory engine would be the first path I would consider if I were you.

Second, an LS swap. Depending on your skill level it can be pretty simple when it comes to engine swapping.
 
The Jeep inline sixes really only have one thing to recommend them: They're inline sixes. It's a naturally balanced configuration that's hard to screw up, and so straight six engines tend to be durable, and Jeep's versions are no exception.

In the minus column they're way too heavy, not particularly efficient and have badly outdated fuel and ignition systems. Just check out how many posts you see on all forums pleading for help with mysterious no-start troubles to see the problem.

If you're going to swap a different engine in, the obvious choice is a GM small block because of the huge support that platform enjoys across the board. You can go anywhere from an ignition points and manual choke setup from the early 70s to a modern fuel injected drive-by-wire with no distributor that will always run perfectly under any conditions. Almost any of them will give you more power and economy than the Jeep 6, and most of them will weigh less.

But hey, if Chevy isn't your thing, once you get the stock engine out, just about anything will fit under a YJs hood. 3 cylinder Yanmar marine diesel? Heck, someone's probably done it.