I don't claim to be a mechanic in the least, but I do know that my g/f had her 4.2L Jeep YJ changed from carb. to a 4.0L fuel injected vehicle (It was a '91 Cherokee). That being said, plus all teh stuff everyone has said in this post, I think it's a possibility.

 

Okay, I want to do this for the least amount of $$- so no rush. The reason I'm considering the fuel-injected route (2000 engine) is because it's (the engine etc) free (for now-I'll pay her back eventually). ..but the labor won't be. So this is quite the conundrum...How about just rebuilding the damn engine that's in there?

 

moon, there is a lot larger aftermarket for the jeeps that there is (or isn't actually) for the 4.3L blazer. Edlebrock makes a standalone FI system for the 4.0 I6 that is litterally a 3 wire hookup + an O2 bung in the exhaust.

The reason why I would only recommend installing the short block is because it may be cheaper than rebuilding your lowerend (depending on what's wrong).

Here's some numbers for you. The Re-Main Kit from Napa is right around $200. Who ever would be rebuilding the engine would have to remove it, tear it down, possibly grind the crank (installing oversized bearings for both the rods & mains if they were ground), hone the cylinder walls (or possibly overbore them if they are out of round or warn excessively - this would require new pistons too = $$$). A master rebuild kit which would include new pistons is close to $600.

Now that's just the cost of the parts to rebuild your lower end.

You would have find out exactly if you could use a 2k shortblock with the '91 heads & intake before attempting to do so. Everything that I have read thus far has not said to the contrary, but it hasn't said that it can be done either. The 2k shortblock with the '91 accessories, heads, and intake would be the cheapest route if it would work. And that's simply because it would require the least amount of labor. One thing that I didn't think about is if a '91 waterpump would bolt up to a 2k engine block or if you could use the 2k pump... All things to consider. All of the rest of the accessories should mount to the heads...

 

I love this guy...can you come and work on my truck

 

Been reading your delima.
Are you sure your '91 is a carb?
Almost positive that all 4.3L engines in the S-Series are fuel injected. Even my '87 2.8L engine is fuel injected. The first round of fuel injection looks like a 2 barrel carb, except the fuel injectors are on top of it and shoot down the intake like jets in a carb. Later versions moved the injectors to other places. I even have a fuel injection setup I saved off my 4.3L '91 parts truck. Almost 100% positive yours is fuel injected. That being said.

I think your best option is to pull the engine from the 2000. Swap heads, intake, and all sensors from the '91 to the 2000 block. I would also keep all the accessories from the 2000, starter, battery, alternator, etc. The 4.3L block is the same with a few minor differences. The biggest is the balance shaft, around 93 or so they went to an internal balance shaft. However everything on the outside of the block will still bolt up to either engine. Same motor mounts, tranny bell houseing pattern, even all the acessories are interchangable. There dimensionally the same block. I would use the flywheel and starter off the 2000 to eliminate any possibility of a difference there caused by the internal balance shaft.

Tranny, keep your tranny. It should be a 4L60, might be an early version of the 4L60e. The 2000 has a 4L60E and is the same as the 4L60/700R4 tranny. They are basically the same tranny externally, the major difference in your case is the '00 4L60e is electronic controlled by the pcm. If you run the 60e you will need the computer off the 2000 as well. No need for that.

The pcm in your truck will run that '00 engine, provided you use all the '91 sensors, fuel injection system, and spark control system from the '91. In order to swap the fuel injection systems you will have to swap the intake, and the heads in your case. Simple enough, the heads will bolt right to either engine block without modification, and the intake will bolt to its corresponding heads. Depending on how the '91 heads look, might be worth it to have them cleaned and rebuilt or at least replace any worn parts. That way you have basically a rebuilt engine without all the cost.

Clear as mud.
Post up any questions.

I haven't read your other thread yet, however ususally hearing noise in the crank area is bad, extremely bad. I have a '93 I am attempting to swap out. She makes all sorts of racket in the lower end, runs, but makes a ton of noise. Until I get it out, I am not sure if it is a rod, or bearing. But hey, I paid $50 for the truck and everything else works. Even the a/c.

 

Excellent post.
Exactly, your keeping the internals of the '00 block intact. Thus eliminating any possibility of compatability (internal balance shaft). The 4.3L block externally is exactly the same for all 4.3L engines, even in the fullsize trucks. Same bolt holes in the same locations. To eliminate any possible problems with the water pump, which you shouldn't have and I'll explain next, use the '00 pump. Leave it on the block. The only major difference in water pumps happened when GM went from belts to serpintine belt. The water pump flow direction reversed and the timing cover changed to accomidate the new water pump. As far as I know all 4.3L in the S-series are serpintine belt set-ups. The 4.3L in the fullsize trucks went through the change, however that doesn't apply here. In '87 the 2.8L in the S-series went to serp set-up. The 4.3L didn't appear in the S-series trucks until '88. I am almost positive in '88 the 4.3L was serp belts, and fuel injected.

 

Ok I did some more checking for you. A remanufactured engine from Jasper Engines would cost you $1937 + tax, s&h, etc, but that should be everything but intake up. Another route is a NEW shortblock from GMPartsDirect.com which would be $1,386.06 + s&h (or arm+leg+first born from GMPD.com) and is p/n 12507951.

The reason why I told you that was to point out how much easier it would be to do a swap. Here's a cross-reference list from GMPD.com showing what engines would be a direct drop in replacement (may have different intake setups though):
Now, more on why I am pointing you away from the 2000 block at this point. After seeing some pictures of the older block on Jasper's website, it believe that there may be interference between the balance shaft and the bottom of the intake manifold. Now there might not be, but you wouldn't know until there was significant time invested in doing the swap. That is not to say that things could be worked around. The balance shaft technically does not need to be there. It is commonly removed in the GM 3800 community so that people can run double roller timing chains. The balance shaft is actually another means of counter-balancing the mass of the crankshaft and pistons. If you were to remove the balance shaft from the 2k before putting it into your '91, you may notice more vibrations from the engine... Actually, you might not because your engine doesn't have a balance shaft... I don't know. I'm just saying that there will mostlikely be no adverse effects of removing the balance shaft. I do know that it isn't going to be as simple as removing the shaft itself and starting to put parts back on. There is a pressurized oil feed to the rear bearing for the balance shaft. This hole would need to be plugged.

The deeper that I get into this, the more it looks like you probably should look into either getting a used engine from something on the list above (and it's a big list), or rebuilding yours. If you were to rebuild yours, it would be very adviseable to atleast clean up the heads and put new valve seals on. Valve seals are not expensive by any means, but will make sure that you don't have oil leaking by the valve stem and burning up in the combustion chamber of your nice new engine. You should be able to find some decent engines through Car-Parts.com at a price that would be cheaper than a rebuild kit. The same labor would go into pulling the engine and reinstalling it no matter if you were to rebuild it or swap it with something else. You might even be able to find something at an auto-recycler near you that would put some kind of warranty (30day,3000mile or similar) on the engine to g

 

How did you come up with that cross refference list?
I have been trying to find something like that for my '93 S10-Blazer vin W engine.

 

I just went to the catalog on GMPartsDirect.com, under the mechanical tab. I selected engine --> engine assembly, block & mounts --> then short block off to the right. When you click on the part number, the next page will have an entire cross reference list... Here it is for your '93 vin W although it isn't anywhere near as long as the Vin Z:

**EDIT** What is the difference between vin W & vin Z?

 

I thought it was the injection system, but I could be wrong. All of the "W"'s I have seen were CFI's like mine, and I think the others are TBI. I could definately be wrong tho.