Engine Replacement

[Nightpath]

Someone mentioned the oil pump/pickup on the 4.0 not working with the 4.2L pan.

If I'm doing the full 4.0 / AW4 / 231 conversion is this something I have to contend with??

[DaemonForce]

Do you have to haphazardly attempt to drop in a new 4L to find out? Just do some measuring on the oil pan and you'll see three problems:
• The lowest section of the 4L pan is too big to clear the engine crossmember
• The oil pumps have nearly identical design
• The oil pump pickups use their respective oil pan

There have been issues noted with all three. I'm probably going to go with a 4L oil pump just because I like the bigger selection for this engine but aside from that, the crankcase and pistons, my parts are intended for a 258. Any other combination would be a worse situation than trying to force a square peg through a round hole and you really don't need that kind of headache.

[Nightpath]

I'm using the 4.2L oil pan with my 4.0L (from a 94 XJ) when I do my swap. Do you think I'll come into a problem if I just stick the pan onto my 4.0L?

[mudkicker715]

You sure will. The oil pickup tube stays with the respective pan.

[carnuck]

Each different designed pan must have the matching pump screen with it. It's not hard or rocket science.

[Nightpath]

Never removed any of this before...it's my first swap. I'm an engine swap virgin.

Anything I might need to buy?

[carnuck]

4' long extension and impact quality swivel sockets 1/2", 9/16", 5/8" and 15 mm. Breaker bar and quality ratchet. First time in 4 years I helped do a motor swap between yesterday and today (not quite done) on a '98 GMC 4x4 with Vortec 350.

Avoid doing it on gravel! If you have to, then use thick plywood to roll the hoist on.

Triple check everything is loose and check again as you lift and even go so far as to catalog which bolts go where and take photos to remind you. Bell housing bolts are the worst part. If you have the AC, then the hole for the drain through the floor allows you access to the top center bolt. I do the bottom 2 bolts last (even with the crank and bigger than the others) with the hoist attached and a chain to hold the trans up under the bell. The 2 or 3 small splash pan bolts come off first, then the  Converter bolts and if the trans torque converter pops forward more than 3/4", you will get an ATF shower, even with a drained transmission.
   In the Eagle, if you plan to change motor and trans it is possible to do them together, BUT solid ground keeps you from being crushed by a hoist flipping over. Never do that part alone and preferably with someone strong and experienced if you aren't. Slow and steady keeps you alive!

[Nightpath]

I have a friend who happens to me a 25 year long mechanic doing most of the work (with all required tools). I'm there to do what needs to be done and buy all the necessary parts lol.

As long as the oil pan swap doesn't necessitate buying anything new besides a new gasket I'm happy

I'll be doing a write up with pix after to the swap. Prior to it (this week or so) I'll be making a final post with my plan of action, the parts I'm buying, and so on, so I can be picked apart to ensure it's done smoothly.

[Baskinator]

I have to find the link on my personal computer at home, but I came across an engine building company on the west coast that sells 4.6l stroker engines for $2000 shipped and something like a 60,000 or 100,000 mile warranty (with certified mechanic installation).

[DaemonForce]

That would be a pretty big waste of money if the builder didn't know they're making it for an AMC. Might want to keep that in mind. :/

[eaglefreek]

That would be a pretty big waste of money if the builder didn't know they're making it for an AMC. Might want to keep that in mind. :/

Can you clarify that? I'm not understanding what you're trying to say.

[DaemonForce]

Oil pan, belt style, intake/power steering, exhaust...Well, it's not an issue for anyone reading these threads because we fully understand what's going on but the parts and arrangement of accessories that are on a traditional 4.0L directly conflict with simply fitting one into a Hornet or Eagle. It's not a simple drop-in replacement and you know that.

[eaglefreek]

If you were to buy an stroker engine from a builder, it would be a long block so most of that wouldn't matter except for the oil pan and it might not even include that.

[DaemonForce]

When you put it that way it just seems a bit expensive to me. I guess I have more time than money.

[Nightpath]

IMO you'd be better off finding a 4.0 with lower KM sitting in a OBD1 Cherokee that you can hear running. Should be able to dig all that up for $600 or so, snag the whole XJ with the engine, transmission and transfer case.

Buy the gasket set for rebuilding the engine if you have any doubts. Pull the 4.0 apart, have the head checked to see if it needs decking/planing and whatnot. Pull the crank and rods from the 4.2, have them looked at to ensure they aren't crap.

Replace the 4.0 crank and rods with the 4.2L, there's your ghetto stroker. Toss the old 727 and t-case from the Eagle. Slap the newer drivetrain in with OBD1, profit...if you're running that stock trans and t-case with a stroked motor good luck.

That's sort of my plan right now, except the drivetrain is going in and I'm stroking it down the road. I found a XJ that was running for $250 (body rusted to snot), buying the rest of what I need for around $250-300 (engine runs nicely), and all I need to do now is the swap.

For the price of a rebuilt engine, you can have a much beefier and better performing car with a lot of new goodies under the hood. If you have more time than anything, than you know that making a few low cost local purchases is where it's at. Take a look at options you can do locally before blowing a huge wad of cash on a rebuilt motor.

Take the time to do it right and you get exactly what you want...and you can modernize your Eagle for less in the process