Everything Isuzu but the chassis and body? (4JB1-T thread)

[Senorbarbo]

Hi all,


I’m Javier López. a Spaniard quite obsessed with Landies since I was a child… and that was a long time ago.


For years now, I have been working on the possibility of using the 4JB1-T on a Series. I wanted to offer a complete solution for old Landies. This engine is light, efficient, reliable, and the spare parts are ubiquitous… and it has just enough power to bring a Series close to modern performance on open roads.


However, when it comes to swapping the engine, I found that the original LR gearbox would not withstand the torque, so I researched gearboxes. Then I concluded that the best solution were the gearboxes which already were matching the engine. Then, I discovered that it was neither easy nor cheap to match the MSA gearboxes with the LT76 transfer. I realized that the best option would be to use an Isuzu gearbox + transfer. But then I found out that the Isuzu gearbox output of the transfer would not match the rear differential (they are not aligned). So, I thought that if you are going to purchase the engine, the gearbox, and the transfer, wouldn’t it be best to replace the axles as well? The Isuzu front one has disc brakes, which is something you should do anyway if you swap the engine, and they are more robust than the originals (the original half shafts will not be happy with 30-40 more HP).


Maintenance would be easier too. If you need body parts, go to LR; for everything related to the drivetrain, engine, and gearbox, go to Isuzu.

Of course, I would need to make two custom drive shafts and adapt the axles and steering bar of the front and rear axles to install it with leaf springs... but it is still the most cost-effective solution with the best performance results.
What’s your input?


Note: Despite being Spanish, and hence my love for Landies, I live in Hong Kong, which is where I have the company. This is why I have easy access to Isuzu 4x4 pickups, which have proven ultra reliable.

[grey_ghost]

Hi,

I am definitely no expert but have you researched the Perentie? (Or Australian Stage one diesel).

Perentie came with either 4BD1 or 4BD1T - coupled with a LT95 gearbox (4 speed) and I believe LT85 (5 speed but apparently less robust)

I love the 4BD1 but it is a very rough vehicle - it would probably shake a Series Land Rover to bits.

Lookup Gromit on here - he has a Series 3 with an Isuzu engine in it, I am not sure which one (it’s not a 4BD1).

Good luck - it sounds like an interesting idea.

Cheers,
GG

[cjc_td5]

The J series Isuzu engines are a nice match for a landy, being a lot lighter than the B series engines in the Perentie etc.

A guy in NSW runs a 4JB1 in his series 3 LWB. He runs the entire engine, gearbox and transfer box unit from a Holden TF Rodeo.

I have a 4JH1 in my series 2, with a MYY5T Isuzu box behind it and a remote mounted LT230 transfer case. Mine is a forward control though, and pretty heavily modified. The 4JH1 has been retrofitted with the mechanical 4JB1 pump and timing gears, which is a popular modification here when the electronic pump in the 4JH1 fails.

To my knowledge, everything sold in OZ with a 4JB1 engine would have an independent front end, so there would not be any readily available front axle to swap in? Toyota front axles work pretty well if considering going that way.

Chris

[Senorbarbo]

Hi,

I am definitely no expert but have you researched the Perentie? (Or Australian Stage one diesel).

Perentie came with either 4BD1 or 4BD1T - coupled with a LT95 gearbox (4 speed) and I believe LT85 (5 speed but apparently less robust)

I love the 4BD1 but it is a very rough vehicle - it would probably shake a Series Land Rover to bits.

Lookup Gromit on here - he has a Series 3 with an Isuzu engine in it, I am not sure which one (it’s not a 4BD1).

Good luck - it sounds like an interesting idea.

Cheers,
GG

Thanks for your input. Yes, of course the Perentie is one of my all time favorites. The 4BD1 (T) is a great engine, but I think for a Series is just too much weight and too shaky being each cylinder almost 1 liter. Thanks for pointing to Gromit.

[Senorbarbo]

The J series Isuzu engines are a nice match for a landy, being a lot lighter than the B series engines in the Perentie etc.

A guy in NSW runs a 4JB1 in his series 3 LWB. He runs the entire engine, gearbox and transfer box unit from a Holden TF Rodeo.

I have a 4JH1 in my series 2, with a MYY5T Isuzu box behind it and a remote mounted LT230 transfer case. Mine is a forward control though, and pretty heavily modified. The 4JH1 has been retrofitted with the mechanical 4JB1 pump and timing gears, which is a popular modification here when the electronic pump in the 4JH1 fails.

To my knowledge, everything sold in OZ with a 4JB1 engine would have an independent front end, so there would not be any readily available front axle to swap in? Toyota front axles work pretty well if considering going that way.

Chris

Veeeeery interesting. Believe it or not I do have a FC too, an ex British military 101" ambulance I bought in Hong Kong with less than 12K km on it. Is a project that will take a lot of time, but I love the thing. You can find it in my IG profile.

The point about getting every bit from the Isuzu is that for me is very easy to buy a complete pick up here. Many of them have low mileage and are being retired with less than 100K. It is a brother of the Holden Rodeo and was made in China by many manufacturers (
Foton SUP, Jinbei Jindian SY10, JiangLing Baodian, Winnerway, ZH6500/ZH1021LU2, Xinkai Century, Autorrad Century.... ). It would be interesting to know how the guy you mention in OZ solved the problem of the output and differential not aligned.

Thanks.

[cjc_td5]

Veeeeery interesting. Believe it or not I do have a FC too, an ex British military 101" ambulance I bought in Hong Kong with less than 12K km on it. Is a project that will take a lot of time, but I love the thing. You can find it in my IG profile.

The point about getting every bit from the Isuzu is that for me is very easy to buy a complete pick up here. Many of them have low mileage and are being retired with less than 100K. It is a brother of the Holden Rodeo and was made in China by many manufacturers (
Foton SUP, Jinbei Jindian SY10, JiangLing Baodian, Winnerway, ZH6500/ZH1021LU2, Xinkai Century, Autorrad Century.... ). It would be interesting to know how the guy you mention in OZ solved the problem of the output and differential not aligned.

Thanks.Nice. Mine is a civilian FC, so 109".
There is a 101" in Perth with a 300tdi in it, and one local with a Cummins and auto box in it.

To my simple engineering mind, does it matter if the flanges are not aligned horizontally? They are already not aligned vertically, and the shaft cannot tell x from y planes, it just spins.... It just introduces more angle in to the joints, being a vector of both x & y planes?
C

[cjc_td5]

Mark's build.

https://youtu.be/hN-DgplvbII'si=lQ1Gm4qerqtNU_Lw

[Senorbarbo]

Nice. Mine is a civilian FC, so 109".
There is a 101" in Perth with a 300tdi in it, and one local with a Cummins and auto box in it.

To my simple engineering mind, does it matter if the flanges are not aligned horizontally? They are already not aligned vertically, and the shaft cannot tell x from y planes, it just spins.... It just introduces more angle in to the joints, being a vector of both x & y planes?
C

There is a lot of literature about it. Dana recommends to keep the angles below 3º per U joint (very conservative), while others say 7º or even higher. But the greater the angle, the risk of vibrations and wear increases, so it is better to keep it as low as possible. Is not the same highway speeds than off road (makes things more critical). Crawling speeds will allow you 25º or more. But at the end, the more straight, the better.

[Senorbarbo]

Mark's build.

https://youtu.be/hN-DgplvbII'si=lQ1Gm4qerqtNU_Lw

WOW! This is a gold mine of information... what a job that family did. I never found it in my searches on YouTube because it never occurred to me to do it with the parameter "holden". THANKS

[cjc_td5]

There is a lot of literature about it. Dana recommends to keep the angles below 3º per U joint (very conservative), while others say 7º or even higher. But the greater the angle, the risk of vibrations and wear increases, so it is better to keep it as low as possible. Is not the same highway speeds than off road (makes things more critical). Crawling speeds will allow you 25º or more. But at the end, the more straight, the better.

I can't imagine you'd be too worried about drive line angles if you run a 101". The drive shaft angles are pretty spunky straight from the factory! LOL [bigsmile]

[gromit]

I have Series III with a C240 Isuzu (as mentioned by Grey Ghost).

A company here made conversion kits for fitting these into Series Land Rovers back in the 70's, it mates to the Series box.
Isuzu C240 powered Series 3 (https://www.aulro.com/afvb/other-powered-series-land-rovers/151959-isuzu-c240-powered-series-3-a.html)

Mine has a high ratio transfer box and is a bit slow off the mark but keeps up with modern traffic.

There are a few cracks in aluminium panels from the vibration !


Colin

[Senorbarbo]

I have Series III with a C240 Isuzu (as mentioned by Grey Ghost).

A company here made conversion kits for fitting these into Series Land Rovers back in the 70's, it mates to the Series box.
Isuzu C240 powered Series 3 (https://www.aulro.com/afvb/other-powered-series-land-rovers/151959-isuzu-c240-powered-series-3-a.html)

Mine has a high ratio transfer box and is a bit slow off the mark but keeps up with modern traffic.

There are a few cracks in aluminium panels from the vibration !


Colin

Thanks ! This forum is probably the best all around source of information for LR modifications. And people is very helpful !

[cjc_td5]

Javier, I am interested that you said you can readily get Chinese copy Isuzu vehicles (and parts). I knew there where Chinese knock off engines, but only as industrial engines. I wonder what the knock off injector pumps are like? They are the hard to source part in OZ, and most are going to need a $2k rebuild now given their age...
Cheers, Chris

[V8Ian]

Is there any backup for the Chineseium ones? Not too many years ago, Cummins engines were going to scrap for want of minor parts, as there was no support for them here. Understandably, Cummins didn't want a bar, of them.

[Senorbarbo]

Javier, I am interested that you said you can readily get Chinese copy Isuzu vehicles (and parts). I knew there where Chinese knock off engines, but only as industrial engines. I wonder what the knock off injector pumps are like? They are the hard to source part in OZ, and most are going to need a $2k rebuild now given their age...
Cheers, Chris


In fact they are not "knock-off" engines, most of the times, but made under license ones. This means that there is a supervision from Isuzu on them, and they are as good as the ones made in Japan. I have a Series equipped with a new Toyota 4Y made in China with 20000 km on it by now, and is smooth and reliable.

being said this, yes, you can get also different qualities and some sort of "knock-offs" when you are in China. Some companies make the "long block" and some others just complete the assembly with lower quality components. I have been purchasing automotive and other e components in China for nearly 20 years, and I have managed many projects of complete and complex products. In other words, in your know what you do and you know how to do it, you can get high quality, not only on engines but on many other products.

Isuzu 4JB1-T is an engine that is being produced right now, you can buy new ones and every single part you need for maintenance. They are being sold to many countries in Asia, Africa and South America, and on this countries they need reliable vehicles and they are not so obsessed about global warming and so on.

Before purchasing an engine and will supervise everything on it, I will make it run, I will check the compression, and I just will buy from established and serious companies. Just one on every 30 companies you can find on alibaba, is a real one. Rest are traders, some serious but most of them not that much.

[Senorbarbo]

Is there any backup for the Chineseium ones? Not too many years ago, Cummins engines were going to scrap for want of minor parts, as there was no support for them here. Understandably, Cummins didn't want a bar, of them.

Check my previous post. I could day the same. If you know how to do things, you will get quality. We do manufacture many things for Landies, and the quality is exceptional, much higher than other parts made in "developed" countries.

[Senorbarbo]

After some research I have found that while it could be very interesting to transplant all the drivetrain and powertrain from a Chinese 4x4 pick-up (many of them are 4JB1T Daihatsu powered Hilux clones, this would involve major works on the chasis, having to move back and reverse at least one crossmember of it.

The benefits on the other hand would be noticeable, as the car would have stronger and more modern mechanics, with countless available and affordable parts almost round the world,. (4JB1Ts and gearboxes are being manufactured nowadays), taking an old Series to at least Japanese 1990's durability and quality standards.

All the material required would be to 3500-5000 US$, and on top of that you would have to add shipping of the parts, import duties and so on, which would be closer to 6000-7000 US$. Perhaps less, but is better not to be that optimistic I see this could work for someone who has some Series laying around, for a kind of serial production.

Anyway, while I have discarded this mod for myself, if anyone wants to think about it and want me to help, you know how to contact me.

Now I will move to another topic, on another siub-forum, which is a swap that we have already proven, which is fitting a Toyota 4Y on a Series.

Thanks for your input!

Javier