Got to mate a 4JB1T Isuzu engine to a R380 gearbox, any help wold be h

[Mr.Who]

Hello everyone!

I am new around, so first I'll introduce myself.

My name is Luis Brenes, I live in Costa Rica and I am a proud owner of two aliminium pets: a '74 Series III 88" called Rocinante (after Don Quixote's horse) and a '87 90 called Magallanes (spanish for Magellan, after Fernando de Magallanes) . For many reasons, Costa Rica is a Land Rover zone, and it's the tropical paradise for Rover Hunting!

Well, here is my story about them, I hope you can light my path about it: The 90 has the 2.5 TD Land Rover engine, but the original LT77 gearbox was replaced with a R380 one. As you may imagine, the 2.5 TD is way underpowered and the R380 expects more torque and HP, so basically the car is a giant turtle. So I am going to fit an Isuzu 4JB1T engine to it.

I've done a few research, as well as my own test and fail approaches, and so far I believe I can do it fair easily if a use a clutch plate and bearing for a 300 Tdi and the rest of the clutch kit (cover and spigot bush) for the Isuzu engine. Just wanted to know if someone has done something similar so I can get a guide to follow.

An important issue is that I have the "short bell house" attached to the R380, so I hope I won't have to use anything else than an adapter plate to do it.

Thanks a lot!

Cheers!

[robhybrid]

as you have a short bell housing r380 already attached to a 2.5td I cant see why the conversion should be any different to that of a lt77.

get ready to take hills in 4th that you currently take in 2nd.

[Aragorn]

I see this swap mentioned quite a bit, but the specs of the 4JB1T dont really look that impressive to me?

It seems to only have 92hp, so not really a great improvement on your current motor, and less than a landrover TDi?

[markyboy]

I've done a few research, as well as my own test and fail approaches, and so far I believe I can do it fair easily if a use a clutch plate and bearing for a 300 Tdi and the rest of the clutch kit (cover and spigot bush) for the Isuzu engine.

Surely you'd need a spigot bush capable of taking the the R380 1st motion shaft but which will fit in the hole in the Isuzu Engine Flywheel?

Unless you're very lucky and the Isuzu one has the correct internal diameter to fit the R380.

Depending upon relative sizes, maybe you could get one or the other machined to fit. If not it shouldn't be too expensive to get one made at an engineering shop.

Mark

[Mr.Who]

Hello again!

I think I am going to use the M&D kit, number 204. Land Rover conversions - M&D Engineering

It includes the adapter plate (or bellhousing if needed), the spigot bearing bush that Markyboy cleverly pointed, and the engine supports, it's a straight forward do it yourself kit.

The good news is that the 300 Tdi clutch disc fits into the 4jb1t flywheel (I just need to check the thickness of it, if it is thicker than the 4jb1t's, I'd just need to build and adapter (we call it "a flanger", don´t know if the word has the same use over there) for the pressure plate, if thinner, the opposite, machine the base a little so the pressure plate goes "deeper", so it gets exactly the exact pressure needed. With this configuration I wouldn't need to find a workaround to modify the power takeoff of the gearbox or build a custom clutch disc (my biggest concern so far, is gone! ) Do you know if the Defender 130 clutch disc differs from the 110 one? I'm planning to use the heaviest duty possible, for endurance sake.

About the specs of the 4jb1t, they certainly are not V8 like, but this engine is tuned for heavy work and long lasting durability (and certainly is fair easier and cheaper to maintain and way more reliable than Land Rover engines, please don´t get me wrong, I love the Land Rover heritage, but sometimes it just hit the pocket too hard to be that faithful). The tuning can be easily improved with a few small mods, like a good intercooler unit, more turbo boosting and a little injection pump adjustment. I've seen a Range Rover Classic with this engine, and it performs better than a 300 Tdi unit, even when the Rangie is a heavier duck.

Thanks a lot for your help, I'll keep you posted!

Cheers!

[Lewis]

Anyone have any info on which vehicles these are fitted to which are available in the UK? Either as an import or from our domestic market. Or does anyone have any leads on a good supplier for the engine itself?

I know they are fitted to JCB JS130 - 160 and some hitachi machines but they obviously have no clutch or gearbox and aren't exactly the ideal tune for driving

Thanks

[callum]

4jb1-t came in troopers 88-91 i think, isuzu pickups, -2000 i think and fronteras, but only for 2 years. there's slight differences between them though. i have a trooper 2.8 in my 110 and got a spare frontera top end from the scrappies, but things like dipstick length, cooler piping are different. The frontera model is intercooled as standard, so its air piping is a wee bit different. inlet manifold, for example is as per the 3.1 4jg2. it also had a egr system, but i didn't bother bringing that home with me.

i'm wondering if you're thinking of the 4bd1 (3.9l), as fitted in the australian market. my jcb knowledge isn't too hot, but i'm assuming they're not running 2.8 motors.

over here, you'll find the 4bd1 in isuzu medium pick ups and box vans. not enormously common place, but findable. if you want to fit one to a defender you might have to find some bits and pieces from australia to make the job easier. i think the sump is different and possibly the oil pick up for off road angles of operation. plenty of info on aulro though.

[Lewis]

i'm wondering if you're thinking of the 4bd1 (3.9l), as fitted in the australian market. my jcb knowledge isn't too hot, but i'm assuming they're not running 2.8 motors.

Yeah thats the one I had in mind, didnt realise this thread was about the 2.8, i'm getting my isuzu nomenclature confused

IIRC they were fitted in perentie (SP?) defenders

[callum]

that's the one. n/a version in the 110 perentie and turbo version in the 6x6 perentie. if you got one from an isuzu van you'd at least get the turbo.

australians seem to like them a lot. you've encouraged me to dig out an old lrw from 1998 with an article featuring them. the servicing guy they interviewed said they had quite a few come back from operations in cambodia which had gone 2-300,000km without a fluid change. they cleaned them up, flushed the fluids and sent back out again.

i've seen a few on ebay in or from range rovers with conversion kits, so someone must have offered a conversion kit at some stage. not sure what their source of engines was. given the amounts people used to spend to get rid of v8's from their range rovers in the 90's, they could well have been fresh crate engines.

would be an interesting engine to have though, can't be too many people running them in land rovers in the uk.

[Lewis]

Thats great info, cheers callum

I remember seeing one in a RRC on ebay a few years ago when I had looked previously. Do you know what model the van was in which these were fitted?

[Bush65]

that's the one. n/a version in the 110 perentie and turbo version in the 6x6 perentie. if you got one from an isuzu van you'd at least get the turbo.

australians seem to like them a lot. you've encouraged me to dig out an old lrw from 1998 with an article featuring them. the servicing guy they interviewed said they had quite a few come back from operations in cambodia which had gone 2-300,000km without a fluid change. they cleaned them up, flushed the fluids and sent back out again.

i've seen a few on ebay in or from range rovers with conversion kits, so someone must have offered a conversion kit at some stage. not sure what their source of engines was. given the amounts people used to spend to get rid of v8's from their range rovers in the 90's, they could well have been fresh crate engines.

would be an interesting engine to have though, can't be too many people running them in land rovers in the uk.

Aussies who are fortunate enough to have an Isuzu 4BD1/T in their Land Rover, love them for their undeniable low down grunt and reliability. They are a little noisier than a 300Tdi, but the big issue is getting a suitable gearbox for a Land Rover.

The NA 4BD1 runs out of power, but a turbo fixes that. The factory turbo version of the engine is 4BD1-T, and beside the turbo has some other differences that make it better. Since a Land Rover is much lighter than what the engine was designed for fitting a turbo to the 4BD1 is not an issue.

When Land Rover fitted the 4BD1 (first in the series 3 stage 1, then in 110's up to about 1989) they used a special flywheel housing and a different bellhousing for the LT95 and LT85 gearboxes. They made changes to the oil filters to clear the front prop shaft and changed the sump on early models (later models, including Perenties use the normal Isuzu sump). The engine mounts are different and the front bump stops are 25mm lower.

The Australian Army still use the Isuzu engine and LT95 (but with tapered roller bearings in transfer case). The Isuzu destroys the heavy duty LT85 gearboxes in quite short time so most here prefer the LT95. Some are having success (taking reasonable care with driving style) with late R380 gearboxes (using a modified LT85/Isuzu bellhousing). Another option is to use the Isuzu gearbox and adapt a transfer case to it.

Both the Isuzu 4JB1T and 4BD1T have conservative tunes. They can reliably produce much more power and torque. The stock 4BD1T produces 121HP at 3000rpm. Given a turbo upgrade to provide enough air, they can produce approximately 300HP at 3000rpm from the stock fuel injection pump (simply adjusted for more fuel). With a modified pump with larger plungers, but stock injectors they will reliably produce 500+HP and run to 5000rpm. The stock head gasket, with stock bolts, is reliable at 40 to 45 psi boost pressure (they blow given 60psi, when you need studs).

[landkeeper]

pm 'vinny' here on lr4x4 he's fitted one to his defender along with a r380 that he modified the input shaft on + he has all the drawings on cad for a conversion plate and can give you all the info on mounts etc

it's a great engine in a defender

[Mr.Who]

pm 'vinny' here on lr4x4 he's fitted one to his defender along with a r380 that he modified the input shaft on + he has all the drawings on cad for a conversion plate and can give you all the info on mounts etc

it's a great engine in a defender

Great! Thanks a lot for the tip!

Cheers!

[Bush65]

pm 'vinny' here on lr4x4 he's fitted one to his defender along with a r380 that he modified the input shaft on + he has all the drawings on cad for a conversion plate and can give you all the info on mounts etc

it's a great engine in a defender

Luis,

From the information that landkeeper gave, I used advanced search with words isuzu and author vinny, which turned up a thread with posts by vinny and some pics of the Isuzu engine in his 90.

Note vinny used the 4JB1T with timing gears. From when I was looking into 4JB1T's the later models with timing belt had better specs (changes in fuel injection system, higher power and torque output).

[Lewis]

The 4BD1T was what I was after really, I wanted a large(ish) capacity, high hp diesel for towing etc. Its to go into an old hilux at present but would eventually migrate into the 110 HiCap I'm intending to put together. I guess the 4JB1T would improve towing ability and general performance over the stock non-turbo yota engine, but if I'm going to do the engine swap I want to do it once and do it right.

Bush65, are there any popular hilux conversions that you are aware of in aus?

[Bush65]

The 4BD1T was what I was after really, I wanted a large(ish) capacity, high hp diesel for towing etc. Its to go into an old hilux at present but would eventually migrate into the 110 HiCap I'm intending to put together. I guess the 4JB1T would improve towing ability and general performance over the stock non-turbo yota engine, but if I'm going to do the engine swap I want to do it once and do it right.

Bush65, are there any popular hilux conversions that you are aware of in aus?

The Hilux is extremely popular in Australia - it is a while since I looked at sales figures, but probably more Hilux are sold here in a week or two than all Land Rover models in a year.

However I don't take very much interest in what is done with them. From the little I have seen, fitting a turbo to NA diesels is often done. Some that have had competition success have used the Toyota quad cam V8 - this V8 is cheap here, produces considerable power and can easily deliver much, much more, but they are not renowned for low down grunt in comparison to v8's of USA origin.

With Toyotas that originally had the 3B diesel engine, it is a pretty straight forward swap to fit the much better 13B or 13BT. If the 13BT fits, then I would assume a 14BT or 15BT (both of which are very good largish displacement 4 cyl diesels) could also fit, but the engine got taller when it changed to overhead cam. 13BT to 15BT is just the family progression over the years with increasing displacement and better technology - 'T' designates turbo.

[Lewis]

Thanks! Thats great knowledge, will look into it as the original motor is really struggling with the load

[Risuzu]

I would like my flywheel (Isuzu 4JB1) to be modified to fit the RRC 300TDI clutch.

Can't find any info where it can be done.

Or what has to be done to it.

I am located in the Netherlands.

Comming munday i am in the UK (Hull - Colsterworth Lincolnshire).