Okay, before you get too involved in tearing stuff out of the engine bay, the first thing you should do is decide whether you want to spend the initial time and money up front to rebuild the engine before you drop it in. All the parts and labor involved are going to increase the amount of money you end up spending, however, the peace of mind knowing that things are going to hold up make it worthwhile.
It's all too easy to crank up the boost on forced induction engines and eventually over-stress any critical component of the engine. Plus, just from a convenience standpoint, it's easier to over-build an engine and gradually increase the power rather than having to pull the engine out and build it over and over to accomodate even modest increases in power and combustion pressures. -Carl
We decided to tear into the engine to see what kind of condition it was in before dropping it into the engine bay. Good thing we checked, as the piston rings were completely shot. As Carl put it, if we had installed it into the Corolla as-is, we would have been able to take care of the mosquito abatement issue in Oakland! It would have smoked like crazy. The other reason is that you never know what kind of maintenance the previous owner did, or did not do to the engine. Cars can sit in the worst conditions in wrecking yards, and can sit there for a LONG time. Remember, if you are getting a 4AGZE from an MR2, the engine is already over 10 years old.
I had picked up an engine from a 1989 Toyota MR2 S/C from a wrecked car a few years before. I paid roughly $1200 for the engine (long block), transmission, half shafts, complete wiring harness, ECU, and other random goodies attached to the engine itself. It reportedly had 80,000 miles on it at the time of the car's untimely death, however, it was tough to tell given the exterior condition of the engine. In hindsight, I strongly suggest getting a front cut from a Japanese Levin GTZ, as it will make your life so much easier, will save you a lot of headaches, and will also most likely save you some money. However, if you are the kind of person who likes a challenge, or are somewhat sadistic, read on.
Here are some picts of the nasty, greasy, engine that I purchased from a wrecking yard called American Automotive in Springfield, Oregon. After plunking down the $1200, they were kind enough to deliver the goods to my garage. This is what I got:
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See, I told ya it was dirty!
We spent an evening tearing all the associated parts off the engine. Before you do that, I strongly recommend you take a camera, and take pictures of everything on the 4A-GZE as you can. Take shots of connections, hoses, electrical wires, parts, bolts, etc., from as many angles and distances as possible, as well as randomly throughout the teardown process. We took some, and those pictures saved us a lot of headache. We also could have (and should have) taken even more. Trust me on this one.
Yep, unless you've had lots of experience tearing down and building one particular type of engine, it's easy to lose track of parts, fasteners, and brackets. The GZE is a bit harder to keep track of just because of the complicated intake tract, compared to the naturally aspirated 4A-GE. -Carl
As for the wiring and hose/vacuum connections, try to mark and label as many things as possible, to make it easier on yourself later on down the road. Also, buy yourself a bunch of sealable (ziplock or similar) bags, 1"-wide masking tape (to label misc. stuff) and a couple of permanent markers. As you tear things off the engine, we sure to either reinstall the bolts/nuts into their respective locations or drop them into a labeled bag. You will be surprised how many of those damn things there are. We thought the swap would only take about 3 weeks or so, but given our time and location differences, we were only able to cram a few hours every few nights into the swap. It ended up taking several months. I don't know about you, but you won't have much luck asking me where a tiny little bolt I removed 3 months ago is supposed to go.
Follow the BGB regarding the teardown process. It details the teardown a lot better than I can, and it'll give you a good idea of how its supposed to go back together, again. After a day's work, you can see the fruits of our labor:
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I've gotta say, George is too adept at disassembling stuff. Maybe Alan and I were getting tired and slowing down by the time George arrived at the shop, but we got down to the bare block at an alarmingly fast rate! Course, George dropped two different bolts in an oil pan full of really old oil, but we'll let that slide. =) -Carl