Ok, here's the dilemna: As I said in an earlier post I have this lower engine knock. I was told it could be very costly-maybe even need a rebuilt engine. So, my sister had a 2000 Blazer w/ the 4.3 Vortec w/ 37,000 mi. on it. She t-boned someone and the ins. co. totalled it out. So now it's a salvage vehicle. So the thing is they let her keep it - but she can't get a free and clear title-so it's useless to try and fix it up. (plus she still owes $$ on it) The engine is fine-only thing it needs is a new condensor and radiator. Big question: Can I put her engine into my '91 Blazer? Hers is fuel-injected, mine is not. But they are both the 4.3 Vortec. Are they compatable, can they be swapped? I know the engine mounts may need to be changed and what about the tranny? Please let me know as she wants to part it out and get rid of it. I have first dibs. It's a shame that the red tape that is involved so we just can't fix that one up-it was loaded and a beautiful truck!

 

The first and most problematic difficulty of the swap would be the electronics. It may be worth looking into using the short block and possibly the heads if your intake and exhaust would mount up. You could probably use the newer exhaust manifolds, but it may require a custom exhaust. You really would have to use your intake manifold and injection or else you would run into computer problems. Your '91 is an OBD1 computer while the 2000 is OBD2. Very different systems...

Again, having never torn down either the 4.3L found in your generation Blazer, nor one that is of the 2000 generation, I can not tell you with all certainty that it would or would not work. In the end, it may be cheaper to have a mechanic you trust tear down the motor and rebuild the bottom end. In your Blazer, it shouldn't be too difficult, but if things are knocking, it is possible that the crank will need turning. A master rebuild kit (which would include all bearings, gaskets, and rings) should only cost about $150 or less (I haven't actually checked...). The labor would be the killer, especially if you need it back ASAP...

Good luck and I hope that you find a better answer from someone with more experience than I do with this engine.

 

THANKS!!!! I don't need it finished in a hurry, but I need to let her know if I want the engine. How long do you think it takes to take an engine out? Did you read my post about the lower-engine knock? Mechanic quoted me 20 hours of labor. Does that seem about right. You see, I'm blond-for real, but not a bimbo. And I'm an only daughter. So my dad who's a part-time gearhead (we hung out at the dragstrip growing up) taught me to change my own oil and spark plugs, brake pads etc. Mechanics would try to screw me over and were always a little miffed when I knew what they were talking about. SO, I know this guy, but I don't know enough to be able to tell if he really knows what he's doing, and if he's padding the costs on this project. I've had him work on my Volvo-he's an ex-Volvo mechanic. And he's always been honest where that's concerned. So to make a long story short-I need to get as much info as I can before I approach another mechanic.

 

If you want to find some good information go to s-series.org and check out the sticky in the 4.3L Engine section. One of them tells about all the model years of 4.3 and is very helpful with what you need to decide.

As far as "Swapping" in the 2000 for the 91 it should be very little trouble for a good mechanic to handle. Since Chevy looks to keep costs down the block should not be any different from your 91 to 2000, so the best bet would be to swap the tranny too. And most of the changes were to the intake and engine management technology (so take all the Electronics ie: computers, wiring harnesses etc.) You might need some fabrication for tranny mount but if you take all the mounts off of the 2000 donor vehicle you might just make it work. One thing might be that the body style changes from 91 to 2000 they might have made some small changes to the frame so motor mounts might have to be reworked also but if you are not in a hurry then this should not be a problem...

 

Oh, and sorry I didn't lump these two threads together "engine knock" and "engine swap". Just kinda found out about the latter being an option (atleast immediately). She wants it off her property-it's stored behind her shop. She was toying with restoring it herslf too. So should I just get someone to tear out the engine until I know what to do (and if it's even possible)? And if I do, what else should I take (I.E. tranny) I just don't want it to be one of those shoulda, coulda moments. And not quite sure what's compatible and needs to stay with that engine in the swap. And again, thank you Kyle for the knowledge you've lent me in all these matters. I'm no drama queen, this just became urgent (engine swap)-I don't want to miss out!

 

You must've responded while I was writing the last post Thank you for the ray of hope. All I was getting from people I had talked to (before I joined this forum) was totally negative. One of my pet peeves is negative know-it-all people (the kind that really don't know s**t) -oooh that ticks me off!!! You guys are totally helping me out!!! If you lived near me I'd bake you all cookies!!

 

the easiest way to do it would probably swap the the whole drivetrain, pcm, and harness because the newer motor has a lot more sensors and solenoids then your 91. it will be very time consuming so plan on a lot of down time. this would actually be a perfect time to swap in a small block. it would go good with that custom paint your sister's planning on. [sm=badbadbad.gif]

 

Just like to help and give hope to someone that needs it....I decided to find the links to s-series.org sticky so that you could find it faster...

http://forums.s-series.org/viewtopic.php?t=41520
4.3L info This link is really in depth as far as talking about where the engine was made and what specific differences were for each year upto 1998. It should give you some better insight into the 4.3L engine that is in the Blazer in general...

http://forums.s-series.org/viewtopic.php?t=12717 4.3L
RPO codes and hp figures...for different years...

 

Hey thanks, cuz I was just there-trying to find the sticky. Came back here to re-read what you wrote because I couldn't remember what I was supposed to look for. I prefer to call it hypoglycemia, not a blond moment...thanks for the shortcut!!

 

After reading through that first link posted by 20Blazer00, it looks like you may possibly be able to use the 2k short block (block, pistons, crank, & cam), but you would definitely have to use your heads and intake. This would be the fairly simple to swap around especially once you had both engines sitting side by side. Then you could use your stock exhaust manifolds, stock intake and all of the stock electronics in your '91.

Good Luck!

**EDIT** That is all hoping that they didn't change the water passages much between the different head designs. The reason why you can't use the 2k heads is because they switched over to angled intake manifold bolts so your intake would not bolt up at all.

**EDIT2** The reason why I didn't go into the replace everything (engine, trans, computer, & associated wiring) is because I am under the impression that you want to do this for the least amount of money to get your blazer back on the road. An engine swap between generations is a huge undertaking requiring LOTS of time, which translates to $$$. At that point, a v8 swap with carb would be easier and cheaper (labor wise) than a 2k drivetrain into a '91.