Isuzu 4JJ1 swap for 300tdi?

[ZIKOMO]

Sadly the head has gone on my 97CSW (again!) and I’m left with the option of reusing that motor with a new head, water pump etc or to swap out for a Dmax 3.0T 4JJ1 with just 35k km.  I appreciate this option means stripping the “new” engine of all the computer parafanalia and going mechanical but just wondering if anyone has or knows of someone who has done this swap?

I’ve always been in favour of keeping the old girl as original as possible but having to change head gaskets more often than cam belts is a pain and I have to admit, a 35-odd% increase in power is quite appealing so any constructive advice would be appreciated please.

Edited December 31, 2017 by ZIKOMO
Typo

[Gazzar]

I know nothing about your dmax engine, is it common rail injection? If so you might have to keep the fuel system. Unless the engine is based on something with mechanical injection that you can still get,  it would be difficult to make something up, getting the timing would be fun. 

M&D engineering do conversion kits for a lot of engines, they may be able to help you with the adaptors.

 

I'm curious as to why the current engine keeps failing, though. It's not a common problem. Can you tell us more about its history? 

 

G.

[miketomcat]

As above I know nothing about these engines. I'd be surprised if you can take the electronics off. Most modern engines will not run mechanically. You may be able to get it running with it's original ecu and engine loom mated to your loom or with a bespoke loom and ecu.

Mike

[ZIKOMO]

I’ve owned the vehicle from new.  I bought it for export in UK, used it there for 11 months for visits and shipped it to the Middle East and on to NZ.  It has now traveled about 210k km, none of it really very hard working.  The head gasket first went at around 100k and the head had to be skimmed for refitting now it’s gone again but this time was pretty dramatic.  Temperature rose VERY suddenly rose going up a fairly long, winding hill with a light dinghy trailer on the back and she blew coolant before the temperature dropped quickly back to normal and remained there.  To all intents it appeared to be an airlock that had sorted itself but just before I reached a service station the engine cut.  I was able to pull off and open the bonnet/hood and she started again but shortly after there was a pressure discharge from the oil filler cap and she died again.  The speed with which the temperature came up makes me wonder if the water pump hasn’t packed a sad and just cresting the hill and cruising down with the kenlow going full chat was why it dropped off so quickly.

I’ve had her delivered to a mate who specialises in building rally cars and re-engining Hilux with supercharged 4l Lexus motors which involves tailoring bellhousings but I’m waiting to hear whether he’s happy to rebuild the 300tdi or we go with an alternative.

I believe the Aussie Perentee was built using the Isuzu 2.8 drivetrain and that this 4JJ1 is a derivative of that but was just wondering if anyone had any experience with it.  If I do go that I will post back with the outcomes.

Happy New Year!

[landroversforever]

It was the 4BD1T in the 6x6 perenties, I think a 3.9L. 

The Dmax lump I reckon is going to be commonrail and will need to keep its ECU etc. 

[landroversforever]

If the 300 is a UK spec car.... were there any changes to them for NZ/Aus market? 

[ZIKOMO]

Good point but she was built to NZ spec and as far as I am aware the only real change was to fit a km speedo

[ZIKOMO]

The 4JJ1 Dmax is indeed a common rail engine so this mightn’t be readily achievable.  The last thing I want is to introduce any electrickery to the car.  Hopefully I’ll get the verdict on the 300 Motor later today - certainly the quickest and most straightforward fix!

[Gazzar]

It should transplant, so. But you'll need the ECU. You also need to know if the ECU needs to believe if it has the rest of the control units on the canbus beside it. You might also need transponders and keys, it depends on the level of anti theft smarts in the Isuzu system. 

More research, I suggest. 

Unfortunately, there is no mega squirt for diesels, otherwise I'd be putting in Volvo d5 engines to my trucks.

Plus, you'd have the usual hassles of maintaining a non standard install.

But, if the ECU is standalone, why not?

Keep us posted, I love to see unusual work like this.

[ZIKOMO]

Thanks for all the feedback and info.  In the end I elected to pass on the Isuzu engine and as when I got the head off the bores etc all looked good, have sourced a new head, gaskets, bolts, core plugs, water pump, thermostat and expansion tank/cap to rebuild the original engine.  I’m also taking this opportunity to change the cam belt and the radiator is away being checked & cleaned at the moment.  Hopefully she’ll be back together next weekend.

The head itself had cracks between the valves on 1 & 2 and to the injector on 2 and there is evidence of some gasket leakage between 2 & 3.  Getting the injectors and glow plugs out was proving to be a mission so they’re on order now and I also found most of the core plugs were weeping in both the head & block.

Pity really, I reckon she’d have been an even more awesome truck with that 4JJ1 in her but in the end practicality and to some extent originality won out.

[Jocklandjohn]

If you're keeping it 'original' and wanting 'more' why not try something like this:

 

http://www.mdengineering.co.uk/shop/engine-performance-upgrades/kit-170-300-tdi-engine-upgrade-from-2-5-litre-to-2-8-litre/

[Simon B]

I think the Isuzu options were;

4JB1T. 2.8 4 cylinder OEM in Aussie defenders at one point

4JG2 3.1 4 cylinder indirect injection. 

4BD1 3.9 4 cylinder direct injection with or without turbo. Fitted I think to some Aussie discos and the military Perentie.

 

I have a 2.8 in my 110, it is a very smooth engine, also used in Vauxhall Frontera. I thought about the 3.9 but had heard it could shake your fillings loose at idle. 

There was also a rumour that Isuzu produced a small number of 4JB1Ts that were bored out to 3.1 just before they went indirect injection. That might be a very nice power plant. 

[Samlandy]

I think you should give it ago. And please be keep in touch with me. I'm thinking it's possible.  I think could possibly us the r380 box and a plate made up to marry them together. There not much different. I would like to get hold of a 4jj1 gearbox to take some measurements. The 4jj1 is a stand alone engine basic ECU set up. 

Edited April 24, 2020 by Samlandy

[Yostumpy]

I too had. 4JB1T 2.8 in my old 110.   Beautifully smooth engine, and revs so freely, and quiet( had a rubberised jacket surrounding the block). When I got the 300 tai, I was shocked, it felt and sounded like an old Thwaites dumper. The Isuzu sounds like a sewing machine by comparison, and went like stink, didn't even have an inter cooler fitted. Heard there was trouble with the 3.1s tho.