4jg2 motor

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mikesj413
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4jg2 motor

Post by mikesj413 »

hey, anyone had any problems with this motor, the ones in the bigshorns, have heard strories and want to know if they are any good or not
thanks
85 sj413 standard with 1600 motor and roll cage
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DaveM
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Re: 4jg2 motor

Post by DaveM »

My old bighorn cracked its head, as did my 2 mates ones. Of course before/after this, it was problem free and very nice to drive, even with 33's on it
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Jezza
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Re: 4jg2 motor

Post by Jezza »

The turbos only last about 120k before the heat shield calls it quits and ##### the turbo, the whine lets you know when its happening. Only other thing I have heard about is cracking heads from overheating.
Other then that, they are a great engine IF maintained properly
Isuzu Mu 3.1TD
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DaveM
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Re: 4jg2 motor

Post by DaveM »

Jezza wrote:The turbos only last about 120k before the heat shield calls it quits and ##### the turbo, the whine lets you know when its happening. Only other thing I have heard about is cracking heads from overheating.
Other then that, they are a great engine IF maintained properly


Mine did 165k, no problems with turbo, and head cracked without ever being overheated in the 90k I owned it.
They seem to be a hit and miss with the motors, theres no way of telling how the last owners have treated them, and they can go bang without warning, even when servicing is done properly, but again, may be the way it was serviced in Japan.
Only other problem I have encountered was the EGR needing removing, and the motors getting a lot of blowby, pressurising the sump.
Ended up putting an oil seperator on mine, and that was the end of my oil use between services
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SupraLux
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Re: 4jg2 motor

Post by SupraLux »

Mine was great - loved it. Good power, nice engine. It had a whiney turbo (well, it whistled on shutdown, not really whiney in use) but I ignored it and the head went around 130k's on it...

YES they do heads... but YES all semi-modern high-output turbo diesel engines from that era do... it seems to be that when the manufacturers were just figuring out how to get great power they were overlooking other things and be it a 1KZ, a 4JG2, a 2.8Mitsi (can't remember the code) or whatever, they all do heads. Its probably lack of maintenance, or maybe the odd inadvertent overheat or a combo of things... but if you're going to get something with one of these motors, put $3k aside just in case.

Do the EGR block mod - I've heard from the engine recon guys that did mine that cylinder #3 gets unusually scored on engines with EGR still fitted, where they don't notice it on engines where its been removed. They couldn't back it up with any science at all, it was just an observation having done quite a few of them.

You'll love how it goes tho... go on, get one :)
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Suza
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Re: 4jg2 motor

Post by Suza »

Mine has done 201000km and I got it 107000km no big problems at all good power sold and relible. But I change the oil every 5000km and keep up with the coolant/anti freeze and most of its running is open road 100kms to the super market. A mate had one that didn't last very long but he wasn't big on maintanece of any sort and thrashed it.
I reakon its like most things if you look after them they do tend to last better
fish
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Re: 4jg2 motor

Post by fish »

hey mine has a bit of blow by.. what do you mean by an oil separator?
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DaveM
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Re: 4jg2 motor

Post by DaveM »

There is a guy in ChCh that makes breather kits for the Isuzu motors, helps remove oil before it can recirculate through the intake manifold again.

Amma motors
19 Horatio Street
Christchurch
03 366 0454 or 0274 379 120 a/h

From another site:
Couple of advantages with the breather kit over catch cans. First it is no maintenance - fit it and forget it - just keeps doing the job indefinitely. Second point it is not just a bottle collecting excess oil. It has a baffle in it and effectively changes the breathing system for the motor. This allows it to stop pressurisation of the sump, and stop all those random oil pressure leaks which can trouble isuzus - fixed every leak on mine which impressed me, as well as draining oil back into sump and cutting down blue smoke.

Unsure if simple catch bottle would achieve this quite as well - be good to get feedback on this - improvements with pressure oil leaks/smoking etc over time from different products. If a cheaper product will do the jobs well, go for it. Be very good to know.
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Jezza
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Re: 4jg2 motor

Post by Jezza »

DaveM wrote:There is a guy in ChCh that makes breather kits for the Isuzu motors, helps remove oil before it can recirculate through the intake manifold again.

Amma motors
19 Horatio Street
Christchurch
03 366 0454 or 0274 379 120 a/h

http://www.trademe.co.nz/Trade-Me-Motors/Car-parts-accessories/Isuzu/auction-147361196.htm Here it is
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mikesj413
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Re: 4jg2 motor

Post by mikesj413 »

Yeah because the old mans 1seized the #4 piston a few weeks back and just wonderd if it was a common thing or not.
85 sj413 standard with 1600 motor and roll cage
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Rural53
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Re: 4jg2 motor

Post by Rural53 »

I agree, good motor if maintaned and not over heated. Mine cracked the liner in #1 and cracked the head, but that was with an exhaust leak on the oil cooler. The guys that put the new liners in mine use cast iron ones (from a Jag) not the chrome lined Isuzu ones.
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