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4JX1 to 4JG2 help please

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4JX1 to 4JG2 help please

Postby jackdriver » Thu Mar 31, 2011 9:52 pm

I have a 2000 Jackaroo (Monterey, Bighorn, whatever else they're called), with 4JX1. The donk has all the usual issues and I want to quit it. The rest of the vehicle is really good and has low mileage. I would like to do an engine conversion, and have the 4JG2 T in mind. The things that I'm concerned about before diving in are the bolt pattern (will the 4JG2 bolt to my existing 5 spd manual bellhousing), engine mounts, sump shape, and wiring. From what I can tell, the 4JG2 didn't have an ECU .
Any info you could give me would be greatly appreciated.
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Re: 4JX1 to 4JG2 help please

Postby bazza2541 » Thu Mar 31, 2011 10:10 pm

Don't do it lad.
Go find a 4JB1 instead. The 2.8 has equal power to the later 3.1 but because it is direct injection it has between 15 and 20% better economy, although it is a bit noisier.
In saying that, both engines will bolt to you existing transmission, you will need to swap the bellhousings. I used my original 3.0 flywheel and clutch. Engine mounts are the same, sump etc. I can't say for the 4JG2 what wiring is involved, but for my 4JB1 conversion all I needed was a wire to the stop solenoid to get the engine running. I cut out the ecu and gutted the loom from the gearbox. It did leave me with a few issues though. I am nearly done with those now.
One other point, swap the oil pressure sender on the donor engine for one out of a 3.0 as the guage works backwards on the old senders.
Your tacho will not work once the engine is changed, but I found a wee unit from the states that allowed me to mate the old motor with the new clocks.
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Re: 4JX1 to 4JG2 help please

Postby geeves » Fri Apr 01, 2011 4:34 am

Can you use the tako from an earlier wagon?
Biggest problem people strike with this conversion is getting the auto to work properly but yours is a 5 speed so no problem.
If it was me I would use the 2.8 as well but theres nothing wrong with a good 4jg2
Sanding your knuckles before starting work can help. That way you cant skin them
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Re: 4JX1 to 4JG2 help please

Postby jackdriver » Sat Apr 02, 2011 1:01 pm

Thanks Bazza and Geeves,
I'd be happy to use 4BJ1. They're easier to find here anyway.
Bazza, what wre the issues you had with the gearbox loom? Mine has the 4WD on-the-fly. I traced the loom around and something is linked to the 4JX1 engine computer. Would that be the speedo?
So I've got all the parts, I'm looking to get a complete UBS as a donor, and I'd be happy enough to use the tacho and even speedo from that if necessary.
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Re: 4JX1 to 4JG2 help please

Postby bazza2541 » Sat Apr 02, 2011 6:15 pm

I pulled the ECU when doing my conversion then traced all the wires going from the ECU to the gearbox and removed them. This meant that I cut the link between the reverse lights and the switch on the gearbox, took a bit of faffing about to find the wires to get it fixed. The SOTF system has its own ECU behind the dash, but the light on the cluster requires an earth from the ECU to stop it flashing. (I haven't looked for this one yet) SOTF will still function but the light in the cluster just flashes. The tacho thing has been thrashed to death over on ITOC with no success, I found a work-around from an American company called Dakota Digital who sent me a doo-hicky-thingy-mabob-watcha-macalit interface jobby that speaks both 4JX1 and 4JB1 and wired up in seconds.
As for the 4JG2, as Mr Geeves says, thete's nothing wrong with it, apart from being thirsty, dirty and harder to tune. ;)
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Re: 4JX1 to 4JG2 help please

Postby jackdriver » Mon Apr 04, 2011 7:59 pm

OK, here goes. I'm now looking for a donor vehicle.
When I'm done I'll post some pics.
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Re: 4JX1 to 4JG2 help please

Postby bazza2541 » Sat Apr 09, 2011 6:06 am

kevo912000 wrote:But sure the 3.1 is far more economical than the 2.8????



No sir. 3.1 uses the older indirect injection method. As a general rule the 3.1 and the 3.0 are fairly close on fuel consumption. My 2.8 is doing near 40mpg.
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Re: 4JX1 to 4JG2 help please

Postby geeves » Sat Apr 09, 2011 12:20 pm

Economy wise the 3.1 is the worst especially if you push it. Its still far better than other comparable diesel vehicles. I would of thought the 3.0 was the most economical due to its advanced injection system and reports here seem to back that up. (until they break anyway) The 2.8 is very good but Im not sure about 40mpg I only get 33 if I drive gentle. We have a 60 mph speed limit not 70 like Britain. To get 40 I would have to drive at 40
Sanding your knuckles before starting work can help. That way you cant skin them
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Re: 4JX1 to 4JG2 help please

Postby jackdriver » Sat Apr 16, 2011 9:08 pm

I can say my bit about the 4JB1 T now.
I picked one up this week in a UBS55, to use as a donor vehicle. It's not intercooled (a few were here in Aus from what I can tell). I picked it up interstate and drove it straight home - nothing like a 1500km journey to see how it goes! Just over 9km/litre. I don't know what that is in mpg, but it's bl#@dy good. With chunky mud tyres the 4JX1 was getting 14.1 km/l. I'm happy. I've just got to get it into the MY2000 now.
i haven't started yet, but the bellhousing on the UBS appears to be cast in 1 piece with the gearbox housing. If the bolt pattern is different, I could be looking at custom making an adaptor plate, figuring out input shaft length/spigot match-up etc...man I hope not! :|
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Re: 4JX1 to 4JG2 help please

Postby geeves » Sun Apr 17, 2011 9:28 am

Youve got a complete donor vehicle. Use the engine trans etc from that and then its only mounts to do. If yours was auto you will need the peddle box and clutch bits as well
Sanding your knuckles before starting work can help. That way you cant skin them
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Re: 4JX1 to 4JG2 help please

Postby jackdriver » Thu Apr 21, 2011 12:30 pm

Trans in the donor has done 303,000km and just starting to make some noise. Running gear in the MY is like new, so I'll persevere if I can. See how we go.
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Re: 4JX1 to 4JG2 help please

Postby bazza2541 » Thu Apr 21, 2011 3:13 pm

Theres a spacer plate on the 4jb1. You need to take that off. The trans from the 4jx1 will bolt right up, but you'll need to cut the dowell down to suit and you'll lose the top 2 bolts. It wasn't a problem for me and I've never heard of it being a problem on any other conversion. I used the clutch and DMF from the 3.0 too.
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Re: 4JX1 to 4JG2 help please

Postby jackdriver » Sun May 01, 2011 9:14 am

Yeah Bazza,
Have discovered the spacer plate works as you said. I bought a 16mm tap and new larger bolts. Tapped the top two holes, then drilled out the top two on the bellhousing so I get to keep them. Engine is all bolted up as of yesterday, now got to get it running.
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Re: 4JX1 to 4JG2 help please

Postby bazza2541 » Mon May 02, 2011 5:38 am

all you need is a switched live to the stop solenoid.
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Re: 4JX1 to 4JG2 help please

Postby 4x4SWANNY » Fri May 06, 2011 7:00 pm

Wow never new the 4jb1t Was a direct injected..Have one in the shed with a fully recon injector pump on it.
So do you think that it would bolt up to my 4jg2 box ok. And yes the 4jg2 is far less economical than the old ubs55 2.8.
Might have to do the swap some time..Glad i looked at this thread...Thanks Guys
Oh well, can some one hook up the winch i cant open my door !!!!!!!!!
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Re: 4JX1 to 4JG2 help please

Postby geeves » Fri May 06, 2011 7:30 pm

Going the other way you have to use the 4jb1 clutch to clear the bellhousing so I doubt there will be a problem.
Sanding your knuckles before starting work can help. That way you cant skin them
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Re: 4JX1 to 4JG2 help please

Postby jackdriver » Sat May 21, 2011 6:59 pm

Update -
Have got all wiring, SOTF, everything working except tacho. Just some tidying up to do. need a short piece of pipe made up to match the exhaust together. it sounds like you're standing next to a spitfire at the moment!
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Re: 4JX1 to 4JG2 help please

Postby 4x4SWANNY » Mon May 23, 2011 10:32 pm

geeves wrote:Going the other way you have to use the 4jb1 clutch to clear the bellhousing so I doubt there will be a problem.

Not sure what you mean geeves...? Do you mean i would have to put the 4jg2 flywheel/pressure plate on the 2.8 motor..?
Oh well, can some one hook up the winch i cant open my door !!!!!!!!!
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Vehicle: Long wheel Base 93 ubs69 3.1 bighorn
33x12.5 rto3s 15inch off road. 265x75 16s on road.
9,000 winch, Customers bars all round including twin pipe Rock sliders
Front Guards and up over back wheels.
custom snorkle, Top mount 2nd alt above A/C pump
pro 530 AM CB, Etrex GPS Handheld UHF
TOOLS; 80 mtrs winch ability including winch cable, 2x snatch blocks. Snig/drag chain.
Lowerd front diff, Custom Ali front bash pan, Custom Gearbox to Mid Cross member Bash plate.
Rear trailing arm bracing.
Raised spare wheel holder. Highlift jack mount on back door.
Reinforced tank bash plate.

Re: 4JX1 to 4JG2 help please

Postby geeves » Tue May 24, 2011 4:01 pm

Probably wont be an issue but fitting the 3.1 to the 2.8 gearbox the flywheel can fowl the bellhousing so the flywheel off the 2.8 has to be used. You should have no problem with clearance but check your starter meshes properly
Sanding your knuckles before starting work can help. That way you cant skin them
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Re: 4JX1 to 4JG2 help please

Postby 4x4SWANNY » Tue May 24, 2011 4:43 pm

Just to clarify I would if i did....Put a 2.8 motor in my ubs69 3.1 body...
Oh well, can some one hook up the winch i cant open my door !!!!!!!!!
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4x4SWANNY
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Posts: 226
Joined: Thu May 05, 2011 10:33 am
Location: Waimate sth island
Age: 37
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Vehicle: Long wheel Base 93 ubs69 3.1 bighorn
33x12.5 rto3s 15inch off road. 265x75 16s on road.
9,000 winch, Customers bars all round including twin pipe Rock sliders
Front Guards and up over back wheels.
custom snorkle, Top mount 2nd alt above A/C pump
pro 530 AM CB, Etrex GPS Handheld UHF
TOOLS; 80 mtrs winch ability including winch cable, 2x snatch blocks. Snig/drag chain.
Lowerd front diff, Custom Ali front bash pan, Custom Gearbox to Mid Cross member Bash plate.
Rear trailing arm bracing.
Raised spare wheel holder. Highlift jack mount on back door.
Reinforced tank bash plate.

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