How do I get the best life out of a 4JX1?

[Gearbe]

Hi All

After owning a TD Wizard with a 4JX1 engine for about two months I have caught up with the typical failure modes the expensive way with a new turbo and new injectors after clouds (and I do mean CLOUDS) of white smoke suddenly appeared out the back end of it! $4k later I'm quite keen to get as much life out of it as I possibly can now that it owes me so much. My feeling is that the 4JX1 is probably a little too clever than it probably should have been but under the right conditions is still a pretty good engine - am I wrong?

Anyway I'm stuck with it now - what are your recommendations for longevity?

[geeves]

I have heard of this engine doing 400k without trouble but not seen proof. As you have seen injectors are a common failing but if you had the correct o rings and sleeves fitted you should have no more trouble ever on this front.
Its strange that the turbo and injectors failed at the same time unless oil contamination took out the turbo. If this was the case I would worry about damage to the bores and bearings as well.
Beyond this oil changes and the main filter (drivers side) every 10000km and use only the best 5w40 or if you can find it 0w40. Change the filter on the passenger side every 50000km do the air and fuel filter every 20000 and there is little more you can do.
Watch out for sensor faults. Nought you can do about them except fix when they break. Theres about 20 of them.

[kerry99]

what is the passenger side filter for?

[Blondini]

Manuel says to change the engine oil every 5.000 km

[bazza2541]

Only way to gaurantee a 4JX1 is to take it out wrap it in cotton wool and put it under your workbench. Horrible horrible things. I often wondered if they would support a direct injection set up? but then the memories come flooding back and I realise how much I love the 4JB1.

[offroad]

but under the right conditions is still a pretty good engine - am I wrong?

Anyway I'm stuck with it now - what are your recommendations for longevity?

Yes your wrong (although they do perform well in the short period that they stay going.)

Sell it now cut your losses. seriously!

I agree that they are both a horrible design and horrible execution of that design.

[geeves]

They are a forerunner of common rail and possibly should of stayed a prototype for a bit longer than they did. The history of the engine makes interesting reading. It was first developed by VW but then Caterpillar got there hands on it by either fair means or foul. The truth on this part is uncertain. They then flogged the rights to both Ford and Isuzu. Ford used this design in the Powerstroke V8 diesel and Isuzu used it where we all know. Im not aware of any other production engines using this technology. Both the Power Stroke and 4jx1 suffered both injector oring and other injector problems but Im not sure if the sensor problems are unique to Isuzu.
The reason for this engine was tightening emissions rules with this engine meeting Euro 3 years before it had to which left other companies struggling to catch up
Running well it is a magic engine with power to burn and economy unmatched even by modern common rail engines.
To keep it running there is 2 bits of advise. Dont skimp on the maintenance. Get acquainted with a specialist that knows these engines well. You shouldnt ever have any more injector issues but diagnosing sensor faults if you are not intimately familiar with this engine will have your mechanic pulling his hair out and charging you for the new toupee.
I asked my favourite specialist about these engines and he sais Isuzu has never made a bad diesel engine. He was rebuilding one of these as I spoke to him