Swapping to Chevy 4.3 V6 engine?

[daniel_buck]

So the engine on the willys I think is starting to show some signs of a headgasket leak (or worse), with what I think is oil in the radiator, and smoking more out the tail pipe, and the radiator cap not holding the pressure anymore (but not overheating!).

I'll probably pop off the head to take a look at the gasket, but eventually even if the engine just needs a new head gasket, I want to put something in there that has more power. The little flathead 4 just barely enough power for daily driving, with the 31" tires, and certainly NOT enough for any day trips out to the desert or mountains where there are hills to navigate. After talking with several folks (including Novak Adapters) the Chevy 4.3 V6 seems to come up alot. So I think that's what I'll go with.




My first thought is to just find an 88 or newer S10/blazer with the 4.3 engine and manual transmission, buy the entire vehicle (I see them on craigs list from 1,500-2,000 in running condition). And just swap over the motor, fuel injection/TBI and all. I'm not so sure that I want fuel injection, but if it all transfers over easilly, I would be fine with that. Using the Novak adapter and motor mounts so that I can still use my transmission and transfer case. Maybe move the radiator over as well (if mine isn't enough to cool the V6). But for now, I'm just talking about the engine itself. Radiator, I can figure that out later. I don't need the power steering, so I wouldn't be trying to swap over any of that.

Basically, I'd like to make this engine swap as painless as possible, I don't want it to drag out for 1/2 a year. (whether I do it now, or in the future).

Thoughts on this?


Anyone ever done something like this? If the engine and TBI/fuel injection is working fine, does it all simply carry over when you put the motor into a different vehicle? No need to retune the computer or anything? TBI is a pretty simple fuel injection, right? Any sensors that are needed for it to work, would already be on the engine itself, so if I just unplug everything going to the engine (throttle cable, fuel line, radiator hoses, and so on) the fuel injection is pretty much all encompassed with the engine? just a matter of mounting the computer in the engine bay somewhere?


(edit, sorry, this went in the wrong section, didn't mean for it to go in the ForSale section!)

[Materdaddy]

(edit, sorry, this went in the wrong section, didn't mean for it to go in the ForSale section!)

What do you mean, it's in the drivetrain section!

[daniel_buck]

Thanks, who ever moved it to the right section

[inVERt'D]

My experience is that you're right to get the entire donor vehicle. When swapping a modern fuel-injected engine into an old carbureted vehicle, there are so many "little" things you'll need that otherwise you'll spend a career in junkyards (and a good bit of money) or a small fortune on stuff from dealers and the aftermarket.

Various thoughts:

I like multiport injection, but TBI is good.

Don't know how big your radiator is, but I'm betting it's not up to cooling the 4.3.

I think the swap will likely take at least a few months to do right even if you are fairly well-prepared ahead of time. Lots of details.

You might want to consider augmenting the frame some, since the 4.3 is torquey. That little thing will give you whiplash when you hook up. Don't kill yourself.

[dirtman13]

I did the 4.3L swap into my CJ. The best thing I did was to get the factory service manuals. Not the Chilton books. These are 3 books each about 3" thick. They have all the info you need. The hardest part is the electrical and mating the two.

Novak Adapters is a great resource for info and parts.

Getting the entire vehicle is a great idea if you have the space. It will make things much easier.

[2blk2drs]

Why would you not want fuel Injection?

Do you like stalling out on steep climbs?

[daniel_buck]

Well I hear of people having headaches dealing with fuel injection. And it seems like alot of complication when a simple carburetor would do just fine. Lots of sensors and stuff to potentially go wrong, right?

Don't get me wrong, I think fuel injection is way better all around, I just want to make sure I don't get in over my head, get everything all installed, and then have trouble with the computer stuff.


I think I have room to get the entire vehicle, I can keep the willys in my garage, the donor S10 and my TJ in the driveway, and then when I'm eventually all done with the S10, have someone tow it out to the junk yard.

Chuck, what did you use for your donor vehicle? What do you mean the hardest part was "mating the two", are you referring to the engine mounting itself? or the electrical stuff?

[Zoobi]

Ive done several chevy v-6 and v-8 f/i motors over the years. The last one being an 04 astro van v6 with computer controlled auto into an 84 toyota pu and having it smog correctly. I use Howell fuel injection for the harness and pcm. They have great customer service, use gm parts and wire colors. Their pcm work is better than anyone else ive had to get involved with. Whatever year you base your build on, their wiring and parts will match the factory service manual.
If you want something simple, look at the older throttle body engines. They have less to fail and are easy to diagnose. Port injection will get you some more power but will be harder to diagnose if you have an issue. Dont forget, these engines are getting older. The throttle plates can have wear and will cause drive-ability issues. Make sure you check things carefully and replace any part your not sure of.

Scott

[dirtman13]

Chuck, what did you use for your donor vehicle? What do you mean the hardest part was "mating the two", are you referring to the engine mounting itself? or the electrical stuff?

I meant mating the electrical from the willy to the new engine. As long as you have those books and a basic understanding of automotive electrical it can be done fairly easily. I used a Painless harness which also has the correct color coding and proper connectors. I did not get the whole vehicle and the wiring was cut at the fire wall.

My engine came from a 99' S-10.

You'll also need to have the anti theft programming removed from ECM. This is not to bad. I paid about $60 to have my ECM reprogrammed. Had them adjust the shift points for the 4L60e while he was in there.

[daniel_buck]

So I wonder, since I still want to use my original transmission (manual, T90) do I need to find a manual transmission S10, or would an auto be ok? the computer is maybe the same, just tuned different?

[dirtman13]

If your going to the referee then you must use a trans that was available on the donor vehicle from the factory. That's why I have a 4L60e. I don't believe you have to worry about that because of the year of your vehicle (willy) but I did.

If you do go with a manual or older non computer trans then you have to have the trans program removed from the ECM .

[inVERt'D]

He doesn't need to worry about SMOG, which is awesome in itself.

dirtman13 is right about the FSMs--they're very useful if not indispensable. Also a lot of the little things I was referring to involved what dirmant13 said: mating the electrical connections. I took used factory harnesses and adapted them. If you have the complete vehicle, or can get a harness for $50, this isn't a bad way to go. Of course, used harnesses OEM harnesses can run several hundred dollars, depending on demand and application, so in that case, the Painless kit doesn't seem so expensive.


I also agree with 2blk2drs: stalling on hill climbs is dangerous. Go factory fuel injected, since there is good factory stuff available for the 4.3s, which is cheaper, and probably better than the aftermarket stuff.

Don't know much about Howell's kits that Zoobi mentioned, but I'd definitely check them out.

Here's what I used:

1) OEM wiring harness(es)
2) Electrical diagrams that match your harness/ application, colored with felt-tip markers for quick reference--worth the trouble!
3) Universal breakout box. Adapter for ECM is nice to have, but not necessary. Make sure the b/o box has enough pin locations.

The breakout box allows you to test the ECM, fuel pump(s) etc., and it also allows you a good way of hooking everything up without actually splicing wires.

If you get the donor vehicle, you want one that's running great. Do you go overhaul/ rebuild the engine anyway? Up to you, but at least you know the whole system works, which could save you lot of trouble.

Various things you can use from the donor vehicle: wiring harness(es) fuse/ relay boxes (along with the fuses and relays), sensors (such as EGO) that aren't attached to the engine, fuel pumps and relays, inertia switch (emergency fuel-pump shutoff), ground cables, etc.,; portions of the exhaust, such as catalytic converters, air injection tubes, EGR junk, etc.; fuel rails and lines, pressure regulator, carbon canister; radiator (might just be adaptable?); probably a bunch of stuff I'm not thinking of, which is in itself a great reason to use a donor vehicle.

Edit:
One thing I neglected to mention is that since the donor vehicle fuel tank will probably not be a good fit, you will probably want a fuel cell that will accommodate your factory in-tank fuel pump. The in-tank pump is probably the most reliable means of feeding the engine.

[dirtman13]

One thing I neglected to mention is that since the donor vehicle fuel tank will probably not be a good fit, you will probably want a fuel cell that will accommodate your factory in-tank fuel pump. The in-tank pump is probably the most reliable means of feeding the engine.

Great information. I will only add that I went for the external in-line fuel pump which I believe is the best route. Not only are they small enough to carry a spare they are much easier to change on the trail in the event of a failure.

Keep in mind that the late model 4.3 needs high gas pressure. 65psi IIRC

[6spdYJ]

If you are interested in something a bit different, several of the US made forklifts have the 4.3 Vortec already equipped with propane. Yeah, you lose a bit of power, but with as light as the little CJ is and as good as the Vortec motor makes power you'll hardly know the difference - except in your wallet.

[daniel_buck]

I've already called a local place to see about making me a custom fuel cell. I'll probably go with an the external in-line pump. That wasy in the mean time I can still use my mechanical pump on the engine that I have, and when I put a new engine in that needs more pressure, I can just put an inline pump.

Interesting, propane I've thought about that, and my main worry would be since it's a daily driver, how easy is it to find a filling station that would be willing to fill up a vehicle's tank?