Yay! Another newb! General (broad) questions on a build

[Brandon_K]

99 TJ 4.0, 140k on the clock

During a normal drive in the park, I launched it a little from a stop sign, 4500rpm and.. knock, knock, knock, knock.... Nothing horrible mind you, I (and a few others that took a listen to it) immediately felt it was a stuck lifter. A Seafoam oil treatment, a little more driving, nada. Fine. I'm literally on my way (~4 miles away) to my buddies house to start tearing it apart and it siezes. 2 hours later AAA rollback shows up and gives me a ride back home.

I'm going to put a junkyard motor in it and figured while it's out, it would be stupid of me not to poor man it, so that's the plan.

Right off the bat, does anyone know somewhat firmly what years are interchangeable? I've talked to one guy, who I have no reason not to believe that said 97-99 TJ blocks will work fine, as will 00-01 XJ blocks. He mentioned that a 00+ TJ block will not go in without a fight and some bootyfab to get the accessories to all mount up again. This would make some sense to me, I mean Kilby's own OBA setup has a specific bracket for 99's w/ AC, so I suppose the 99 really was the black sheep. Atleast I have rotary HVAC controls I suppose.

Anyhow.. Since this is a forum full of people, invevitably some that have a 99 and used a junkyard motor for a quicker build and swap, anyone have any opinions or facts on the above?

As far as the build goes;

4.2 Crank
4.2 Rods (have these)
SP 677P's
Stock everything else

I figured while I'm in there, new bearings, rod and mains (Clevite? Good, bad, otherwise?), unless the junkyard motor I aquire has bearings in good shape. Since I drained nearly a gallon of antifreeze out of my oil pan.... I'm going to skip reusing my old ones. I guess I punched it through somewhere I also had the thought that while the head was off, new FM SP lifters. They're cheap and pulling the head on these while it's in the chassis sucks. Unless the junkyard longblock has some scored walls or other badness, it's going to be a 4.5 build with standard holes, unless someone has a good reason why I should spend the money at the machine shop. (Jeep was my DD, I'm not in a position to go draging a block around at the moment) I'm figuring the donor motor will have ~80k on it.

Eventually I'll throw a set of Ford 24lb/hr injectors in it. From what I understand they're not absolutely required? Currently, I'm laid off, which is why it being my DD isn't a huge ordeal right now. Since the T-case and trans is laying on the floor, I'm putting a NV3550 in it (AX-15 is shot) as well as one of those new mega-ultra-OMG short SYE's. As I said, I'm laid off so money is tight for new toys, hence the poor mans stroker with injectors a little later. I also had to budget for new rubber rings. (Hurry up BFG! Release the KM2's in a 37 on a 15" rim!) New radiator too, as mine has been leaking for a little while now. Go ebay! Single core OE for $80 shipped!

Cliff Notes;

What year motors/chassis's should I be looking to get a donor motor from?
Sources for 4.2 cranks? In my search, there is exactly 2 on car-part. I searched for a 88 Wrangler. Anything else interchange?
Stock injectors ok for a short time (2-3 weeks)?
Any reason other than increased displacement to bore out? (Also saying that the walls are in good condition)

I'm certainly willing to entertain other thoughts anyone may have. I'm not looking for a speed racer, though I won't mind the extra power when I'm trying to pass. It won't hurt spinning the tires to unload them offroad as well.

Sidebar: Anyone running 37's on 4.11's?

[dwg86]

Check you local parts store for a crank(autozone, advance auto parts, or local machine shop. They normally come as a kit with rod and main bearings. You can use the 258 rod bearings, but the 258 main bearings are different. You will need 4.0 main bearings.

PAW Inc. sells reconditioned 258 rods for $60.00. $90.00 with ARP rod bolts. I don't know about the quality, but you can't beat those prices. I paid $94.00 just to have my rods reconditioned. That didn't include the price for the ARP rod bolts, or shot peening.

Check you head for cracks. That may be where the ani-freeze came from. The early 0331 heads are know to crack.

I would install new pistons. I have heard some talk about piston slap in the 4.0 and have seen a couple of cracked pistons.

Performance mods? That all depends on how much you want to spend. You could do some light port work(just smooth out the ports). A new cam couldn't hurt. Personally I wouldn't want to reuse a 140,000 mile cam... but if it checks out good and money is tight, use it. Just don't expect a BIG power difference using a stock cam in a stroker. I would use new lifters even if you reuse your old cam.

[Brandon_K]

Thanks for the reply dwg.

I looked online at Advance Auto and they said the crank isn't available. Maybe I'll run into the store, then run next door to Advance. And thanks for the heads up on the bearings. I didn't think that the 4.2 mains wouldn't work.

I already have the rods, got a set of 6 on ebay last night for $60, reconditioned. I would assume the bolts that come with them are OE.

Nothing at all other than the accessories off of the old motor is going to be used. It's going straight to the scrap yard. I've been looking around locally and I've found a few motors with 80k on them (or less) for ~$500. The cam is (planning on) going to be reused from the salvage yard motor. Like I said, I'm not looking to be a street racer, I'm sure the increase in displacement will make me happy enough with new found power.

Anyone else have any thoughts? Especially on what years I can pull donor motors from.

[dwg86]

Not sure on what year blocks will fit. You can try doing a google search for remanufactured engines. Some of the companies list block casting numbers and years that will fit your vehicle.

Also google remanufactured crankshafts. There are a few companies like Standard Crankshaft and Crankshaft Rebuilders that may have a crank. If you get a crank off car-parts.com, you will have to pay shipping and then money to have it turned. My crank is at the machine shop right now...$130.00 to have it machined.

[Brandon_K]

I found a crank, he's asking $75 but I can probably get him down to $50 as it's a bit of a hike. Said the journals all look great, but I'm still going to take it to the machine shop and have them mangaflux it and check it out. I'm still not sure if it's a 12 or 4 weight, he hasn't responded back to me with that.

Also decided I'm going to do a cam. From the further research I've done, apparently the cams starting in 99 are extremely restrictive to get a more complete burn and reduce emissions.