Thought I would put together a detailed thread for the novice/and seasoned Isuzu owners that are considering doing a 2.8L to 3.4L swap in a 1st Gen. Trooper. The subject I did this swap on was æK9TroopinsÆ 1991 Canadian built 2.8/mua5 Trooper. The new mill was a 3.4L out of a Æ93-Æ95 Camaro (Exact year unknown). I also picked up a 4.3L Throttle body (also exact year unknown) to replace the 2.8L TBI. I did this to take care of any ôleanö problems with the increased demand of the 3.4.

I picked up the 3.4 from a local Camaro salvage that had a so called ôgoodö core for $150 (only guarantee was on the block itÆs self). I then dropped it off at the machine shop down the road. I got a call a couple days later saying the crank was bad. I called the salvage and told him about the crank and he said he MIGHT have another one lying around for $50. The Machine shop HAD one for $100 ready to go. I called KT and he said go with the one from the machine shop.

The day KT arrived here in Tulsa after driving 9 hours from Illinois I picked up the rebuilt block and met KT for the first time. We drove over to my friends house that let me use his heated shop. And thank God for that because we had a nasty ice storm that weekend knocking out power to 250,000 people in our area and the surrounding areas. The last day of the swap I spent working inside the shop, in the pitch black with a flash light, but at least I was dry.


The Subject:



The New Engine:


A list of items that were bought for the swap include:
Engine core
Complete rebuild on engine
4.3L TB
New oil pump
All new fluids
New fan belt
Cap, rotor, wires, and plugs. (plugs were bought for a 3.4L and the rest was for a 2.8L)
New hoses
4.3 TB gasket
New gaskets
Starter shims
Starter relocation jig
New clutch, pressure plate and throw out bearing


The first thing on the agenda was to get the old worn out 2.8 out of the truck. Pretty straight forward, just remember were everything goes that you take off. It is easiest to just drop all four of the bolts holding the axle in place and let it find its resting point. It allowed plenty of room for the oil pan to clear.




I was a little concerned with how long it was going to take me to gasket match the 4.3 TB to the 2.8 intake but it wasnÆt too bad. I used three different grinding bits on an air grinder. First I started with the barrel shaped cutter to remove the biggest part of the material. Since the intake tapers to a smaller hole, I used the cone shaped cutter to make it a smooth transaction. Once the holes were opened up to the correct size I used the fine barrel cutter to polish the two ports. This process is very straight forward and anyone can do it as long as you have the right tools, including a compressor that can keep up. In my case I used a 60 gal two stage commercial compressor. The smaller compressors will struggle to keep up and it will take longer. From start to finish on the porting (not including cleanup) it took only about 30 min.










Next I set up the Starter Jig that was purchased from http://www.rodneydickman.com/n101.html
The Jig made drilling the holes very simple just using the supplied instructions. However, I found out later that the starter needed shimmed about 3/16ö, which to me is a lot. I donÆt know if this has anything to do with a defect in the jig or if it is an isolated case but be prepared to do some shimming. This brings me to another point. Do your self a favor and trim off the starter hole in the dust plate that goes behind the flywheel. If not it will not allow you to shim the starter enough.




[img]http://i150.photobucket.com/albums/s120/4xtoy/danas%20engine%20swap/starterjig3.jpg[/img]

[img]http://i150.photobucket.com/albums/s120/4xtoy/danas%20engine%20swap/starterjig4.jpg[/img]

[img]http://i150.photobucket.com/albums/s120/4xtoy/danas%20engine%20swap/starterjig5.jpg[/img]

Notice the bevel on the end of the block. The outer part of the starter hangs past this and has the potential to put a lot of stress on the starter if you over tighten it. You should dab some blue lock-tite on the bolt and just snug it to the block. Also be sure to lock-tite the inner bolt and get it good and tight since it will be taking more stress due to the outer lip.

I then installed the new oil pump but reused the 2.8 pickup tube. To position the screen in the correct location you should get a measurement from the oil pan mounting surface on the block to the bottom of the screen. I used a straight edge to transfer the depth of the screen to the edge of the block surface. To be certain it doesnÆt move, I tack welded it to the pump body. I forgot to get pics of this process but it is pretty straight forward. If you weld the tube on the block be sure and cover the exposed crank case area to avoid getting any slag in it.

The new 3.4 block had two small holes about ¥ö in dia. One was on the top of the block above the timing cover and the other was on the passenger side near the motor mount that went into the crankcase. From all of my research on the 3.4Æs I never heard of either of these holes. My solution was to drive in expansion plugs coated with gray RTV. I did have to enlarge the plugs slightly because all I could source locally was a ¥ö plug and the hole was a metric equivalent, slightly larger. I used a 3/8Æs drive snap-on extension and drove it inside the cup enlarging it just enough to fit tight in the holes. You will also need to plug the small threaded holes with a bolt. The lower bolt hole on the side of the block, I plugged it with a 6mm stud which I used to also attach the four ground wires to the block on that side.
[img]http://i150.photobucket.com/albums/s120/4xtoy/danas%20engine%20swap/34holefrontofblock.jpg[/img]

[img]http://i150.photobucket.com/albums/s120/4xtoy/danas%20engine%20swap/34holeplugflared.jpg[/img]

[img]http://i150.photobucket.com/albums/s120/4xtoy/danas%20engine%20swap/34holefrontofblockplugged.jpg[/img]

[img]http://i150.photobucket.com/albums/s120/4xtoy/danas%20engine%20swap/34holesideofblockplugged.jpg[/img]


Once the starter was on and intake ported and the holes plugged, I moved all of the 2.8 components over to the 3.4. This included the accessories, oil pan, valve covers, intake, exhaust manifolds, timing cover/water pump, distributor, and starter. This is also the time to replace your clutch and have your flywheel turned if needed, or you can just reinstall yours but you will need a 24 tooth pilot shaft alignment tool to make sure the transmission pilot shaft will line up. (If you have an automatic, your life will be so much easier).
[img]http://i150.photobucket.com/albums/s120/4xtoy/danas%20engine%20swap/34assembled.jpg[/img]

[img]http://i150.photobucket.com/albums/s120/4xtoy/danas%20engine%20swap/34assembled2.jpg[/img]

[img]http://i150.photobucket.com/albums/s120/4xtoy/danas%20engine%20swap/clutch.jpg[/img]

[img]http://i150.photobucket.com/albums/s120/4xtoy/danas%20engine%20swap/starter.jpg[/img]

Next we move on to the Throttle body, cable bracket modification. There has been some debate on having to use the 4.3 bracket with the 4.3tb. I found this not to be necessary and used the 2.8 bracket and drilled and tapped three bolt holes on the new 4.3tb. I had to drill one hole in the bracket closer inward and cut the outer most hole off of the bracket since it was too far out. I then marked the holes onto the TB and I set it up in the drill press being very careful to get it level. I drilled the three 1/4x20 holes and then had to clearance the bottom lip to allow the throttle to fully open. I then bolted the bracket on. And tested it through itÆs entire cycle. I had to drill out the hole on the throttle cable slightly bigger to fit the larger dia. Pin on the TB. I retained it with an approriate sized æeÆ clip. If you have a auto with a TV cable (Not sure if they have one or not) this set up will require more modification since there is one lower tab missing on the 4.3
Another point to pay attention to is the type of TPS that you get with the 4.3 unit since there are two types, you should match the one that is on the 2.8TB of ease of installation.
On the left is the 4.3TB and the right is the 2.8TB
[img]http://i150.photobucket.com/albums/s120/4xtoy/danas%20engine%20swap/throttlebodycomparison.jpg[/img]
2.8 linkage
[img]http://i150.photobucket.com/albums/s120/4xtoy/danas%20engine%20swap/throttlebodylinkage28.jpg[/img]
4.3 linkage
[img]http://i150.photobucket.com/albums/s120/4xtoy/danas%20engine%20swap/throttlebodylinkage43.jpg[/img]

[img]http://i150.photobucket.com/albums/...20swap/throttlebodybracket28modified.jpg[/img]

[img]http://i150.photobucket.com/albums/s120/4xtoy/danas%20engine%20swap/throttlebodybracket1.jpg[/img]

[img]http://i150.photobucket.com/albums/s120/4xtoy/danas%20engine%20swap/throttlebodybracket2.jpg[/img]

[img]http://i150.photobucket.com/albums/s120/4xtoy/danas%20engine%20swap/throttlebodybracket3.jpg[/img]



Before you stab the distributor you should prime the engine using the oil pump drive shaft. I taped a socket to a 12ö extension to ensure it would not fall off in the block. I used a electric drill with a 3/8 drive adapter into the extension and rotated it for several seconds to fill all of the oil journals. I then brought up the #1 piston to TDC and stabbed the distributor to point directly at the #1 cylinder. This may take several attempts because not only does it have to line up with #1 but it also needs to line up with the oil pump shaft. Tighten the retainer just enough to keep the distributor snug but still movable.

The motor mounts will only utilize two of the holes in the brackets. The 3.4 has a different configuration which leads me to the next problem I ran into. The 2.8 had an external oil cooler but it had been bypassed on this motor by looping one of the lines back into itself. This cooler could no longer be used due to the 3.4 having two motor mount bosses in the way of the cooler line. I guess I could have cut the bosses off but since it was not being used I took the adapter off of one end and cut off one end and threaded and tapped the hole with a 1/8öNPT and plugged it. On the bolt side, my first choice was to replace the bolt with a shorter one but it was a dealer item only and the bolt was 3 days away. (not an option). So I decided to get creative. My first attempt failed but I ended up cutting off the end of the hose that the bolt went through and tapped and plugged the hole just like the other. The first attempt I welded up the holes in the bolts thinking it would seal the oil from leaking past the bolt. DONÆT DO THIS. After I did it I realized the bottom holes had to be in there to allow oil into the filter. So I re-drilled them fixing my screw up. But like I said, It would be better to just get the shorter bolt to replace the longer one if yours has the cooler option.
[img]http://i150.photobucket.com/albums/s120/4xtoy/danas%20engine%20swap/oilcoolermod5.jpg[/img]

[img]http://i150.photobucket.com/albums/s120/4xtoy/danas%20engine%20swap/oilcoolermod.jpg[/img]

[img]http://i150.photobucket.com/albums/s120/4xtoy/danas%20engine%20swap/oilcoolermod2.jpg[/img]

[img]http://i150.photobucket.com/albums/s120/4xtoy/danas%20engine%20swap/oilcoolermod3.jpg[/img]

[img]http://i150.photobucket.com/albums/s120/4xtoy/danas%20engine%20swap/oilfilterbolt1.jpg[/img]

After Everything I could install outside of the engine bay was done it was time to stab the engine. With the 5spd trans. It is necessary to move the trans. back a few inches to be able to line up the pilot shaft once the engine is in place. I got the engine back in the truck and proceeded to hook everything back up with new hoses and a new belt. I got the throttle cable hooked up and cycled it using the gas pedal and everything was smooth.
[img]http://i150.photobucket.com/albums/s120/4xtoy/danas%20engine%20swap/newmotorin.jpg[/img]

Now for some reason I had a very difficult time getting the transmission to go back in. I still donÆt know what the problem was but I think it had something to do with the pressure plate wanting to engage the clutch. Normally I shouldnÆt have to let pressure off of the slave cylinder to get the trans in but this time I did. Once I removed the slave cylinder We got the bell housing with in ¢ö of the block but it still didnÆt want to seat. We ended up having to put the bolts in the dowel pin holes and slowly and evenly bring the trans. closer to the block until it mated up. Unfortunately it was necessary to bled the hydraulic clutch system. This is a very long process that I donÆt wish upon anyone. A better way may have been a vacuum bleeder system which I didnÆt have.

Finally it was time to start it for the first time. This is when I discovered that the starter needed a lot of shimming. Once I worked out that little problem and a few others, it was back to starting it. At first it didnÆt want to start so I swapped out the TPS from the 2.8 and after adjustment it fired right up. We set the timing at 10* BTDC and it fired instantly after that. I worked out a few more bugs then went on itÆs maiden voyage around the block and after returning I rechecked everything again.
[img]http://i150.photobucket.com/albums/s120/4xtoy/danas%20engine%20swap/enginecomplete.jpg[/img]

At last, it was off for a 400 mile break in back to Illinois.

I would like to thank Ed Mc for his packet of information he sent me to study up on before I did this swap. There was a lot of good info in there. If anyone else has good HARD FACT info to add to this thread pertaining to swapping a 3.4 in a Trooper, please do so. But if it is ôjust hear-sayö or Rodeo related, please specify so. I would like this write up to be used as a tool for anyone else doing this swap.


Chad

Hi...I'm KT

I'd like to thank 4xToy for all his help and for puttin up with me and my dog pestering him for 4 days! <img src="/forums/images/graemlins/lol.gif" alt="" /> Not like we had much else to go do!

The Trooper drove like a dream on the way home and is continuing to do the same now. I have the hubs fixed now and when I'm off in a couple days, i will be testing the 3.4 out in a local mudhole.

Thanks again! Take care and keep the rubber side down.

Dana <img src="/forums/images/graemlins/patriot.gif" alt="" /> <img src="/forums/images/graemlins/patriot.gif" alt="" /> <img src="/forums/images/graemlins/patriot.gif" alt="" />

That mysterious hole near the water pump is most likely for the cam position sensor, which of course you don't need. It would be nice if the distributor would fit there, nice and accessible in the front like a Ford!

FYI, if using a Camaro/Firebird 3.4 it's easiest just to snip the cam sensor & crank sensor wires and leave them to plug the holes.

If you want a cleaner install, GM does sell plugs for those holes, as follows:

9421749 PLUG CUP, CRANK SENSOR 3/4" OD

94033681 PLUG CUP, CAM SENSOR 20MM OD

Cheers & Merry Christmas..........ed

Thanks for posting the P/N's for those Ed. I never read any mention of them in any write ups so I was kinda blind sided by it. Like I said in the write up, in a pinch, you can use a 3/4" plug in place of the metric one but you have to flare it out a tad.

Howdy Gang...

Will this work with the LQ1 V6? 3.4L DOHC... Gonna replace my 2.8 with one... Would it be better to go with the MPFI or the 4.3 TBI?

Thoughts...

The TBI and DOHC MPFI are totally different. A TBI intake won't fit the DOHC (or OHV MPFI) heads. The DOHC is a wider engine than the OHV, another consideration.

A great thread and I will move it to the Archives in a couple of days.

It is a little late for you now, but a speed bleeder makes bleeding a clutch nearly painless. I did mine this week after re-installing the tranny in less than 3 minutes, literally.

For those who are not familiar with speed bleeders, they come from a variety of suppliers and are bleeder valves with a check ball. You open the bleeder, attach a drain tube, and depress the clutch about three times, refill the reservoir, and repeat about 3-4 times. Job done. No need to continually open and close the bleeder.

I also have speed bleeders on all of my brakes. They make the job of bleeding brakes so painless that I flush the system yearly.

Guess I need to do some math and figure out what this thing was setup for... but it is a transverse motor so its gonna be fun either way

Have a good one and Thanks