skipofthedump

New Member
Hi, first post but I've been knocking about the articles when I've had issues with my old defender.

I've not had my '89 200tdi 90 long, done a bit of greenlaning and trundled about. However the truck was cheap and the engine is on the verge of total death.

My question: I want a different engine, capable of cruising the motorways as well as being a good workhorse and off roader. Ive been told that I can pretty much straight swap a disco 300tdi engine and gearbox. Is this a good plan? What would you recommend? What should I look for in an engine?

My experience has mainly been with old range rovers and more recently Freelanders. I'm a fair amateur mechanic and will be doing this mostly myself, I have garage space and the basic tools.

Any and all advice welcome.
 
Welcome
head job, new rings and shells and she'll be good for another 100k
I'd probably do this to the engine when I've got it out. I'm not one to chuck it. However, I do a fair few miles on the motorway and I'd like to hit 70. It's felt a little mean to have the old girl reving like a mad lass.
 
You'd probably be better off getting something more suitable for the motorway use and keeping the 30+ year old Landy for stuff it's suitable for.

I say this as the owner of an '85 110.
 
Is a 300tdi any more powerful?
My son has a 200tdi and that will do 70 on the motorway. You are running out of gears nevermind engine power.
 
I'll echo @Grebby on this. Your 1989, 90 isn't really suitable for motorway work, however, it can be set up.
The 1989 90 wasn't fitted with a 200tdi, these were later engines from the Defender.

Fitting a 300tdi won't give you much of an advantage although they can be improved with a VNT turbo and a larger intercooler along with a properly set up FiP.
The R380 gearboxes fitted to the 300tdi don't offer much of a difference to the LT77's on the 200tdi, the main increase (in top speed) is found with a higher ratio LT230, transfer box.
The R380 does have a better oil pump and more support bearings on the layshafts/better syncromesh etc.

You can get a refurbed gearbox with a taller 5th gear and with the standard 1.4:1 LT230 will give you pretty much what you are looking for.
The Disco engine won't bolt straight in BTW, it takes a bit of firkling...

There you go, that'll be around £4 to £5000 please ... plus a donor 300tdi engine.
 
I have in my Series 2 109 with ninety axles (without the boingy springs) a 300tdi lt77 and a LT230.
Firts question, what tires do you use?
I have the 235/85R16
firts I had a 1.6 ratio LT230 that was strong but fast? Noway!
Second a 1.4 ratio, that is much better. But could still start in second gear and had never power issues on the highway, 120 km/h (75 mph)was no problem. Would it go faster, I don’t know?
Now I have rebuild the LT230 to a 1.3 ratio and fifth gear I can use while driving over 60km/h (37 mph). Going on to the highway I drive over 90km/h (55 mph) before I use the fifth gear
I would not suggest a 1.2 ratio.
Btw my enige has done over a 300k and the turbo is not in the best shape ;)
I have done in my series 2 a 130km/h (80 mph) but that wasn’t the end.

Just a link you can use . Find out the specs from the engine, gearbox/transferbox AND difs.


Cheers Rob
 
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A positive thing in my configuration with the LT230:

I can use the fourth gear in the mountains while towing my caravan and stay in front of the “big-boy’s of the highway”.

The fifth is more like the old fashion overdrive.
 
I'd probably do this to the engine when I've got it out. I'm not one to chuck it. However, I do a fair few miles on the motorway and I'd like to hit 70. It's felt a little mean to have the old girl reving like a mad lass.
Is a 300tdi any more powerful?
My son has a 200tdi and that will do 70 on the motorway. You are running out of gears nevermind engine power.


I do about 30k miles a year in in my '89 110 with disco 200tdi. I run the original lt77 gearbox and a 1.2 discovery transfer box and 265/75 tyres. this will sit at 70 all day with no issues. A 300tdi has the same power and revs as the 200tdi, if you do not like the high revs it is the gearing that needs to be looked at not the engine (other than the engine issues you vaguely mention).
What specifically is wrong with your engine to mean it is on its last legs, my last engine got to 380k miles and was only removed due to an engine fire, the engine itself was still going strong with no issues.

I would not suggest a 1.2 ratio.

I would as a rule disagree with the above, the 1.2 is fine and was the standard fitment to discoveries which were expected to do more motorway miles and less workhorse miles. But the suitability of a 1.2 depends on usage. If you regularly tow 3.5t then I would not suggest one either, if you live in the mountains again not ideal. A 1.2 box will do all of those things but if done regularly you are better off sacrificing some of the cruising for better usability in those conditions. If your main use is UK motorway then I fully recommend. a 1.2 box and I have had one for about 10 years. I can still tow a fully laden car trailer to move around other land rovers and the tractor, and it still performs well offroad etc, but it also sits at an indicated 70 on the motorway with little drama for hours at a time.
 
I do about 30k miles a year in in my '89 110 with disco 200tdi. I run the original lt77 gearbox and a 1.2 discovery transfer box and 265/75 tyres. this will sit at 70 all day with no issues. A 300tdi has the same power and revs as the 200tdi, if you do not like the high revs it is the gearing that needs to be looked at not the engine (other than the engine issues you vaguely mention).
What specifically is wrong with your engine to mean it is on its last legs, my last engine got to 380k miles and was only removed due to an engine fire, the engine itself was still going strong with no issues.



I would as a rule disagree with the above, the 1.2 is fine and was the standard fitment to discoveries which were expected to do more motorway miles and less workhorse miles. But the suitability of a 1.2 depends on usage. If you regularly tow 3.5t then I would not suggest one either, if you live in the mountains again not ideal. A 1.2 box will do all of those things but if done regularly you are better off sacrificing some of the cruising for better usability in those conditions. If your main use is UK motorway then I fully recommend. a 1.2 box and I have had one for about 10 years. I can still tow a fully laden car trailer to move around other land rovers and the tractor, and it still performs well offroad etc, but it also sits at an indicated 70 on the motorway with little drama for hours at a time.
Forgot to mention my son's has a 1.2 transfer box and I also agree it is fine for all his driving. I would say the longer gear on 1st is beneficial. My Td5 1st gear is almost a waste of time, as soon as you are moving it's then straight into 2nd.
 
Cheers for all the replies, here is the engine, I will be taking a lot at the internals within the next week or so. I think I'm missing at least one cylinder ....I was told it was a 200, but as I mentioned I'm new to the defenders. Again all input appreciated
IMG20241108082111.jpg
 

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Also I'm clarifying that the mile I do on the motorway are generally towards spots where I'll need the off road capabilities. Off climbing in Portugal next spring for example and greenlaning in Scotland
 
Also I'm clarifying that the mile I do on the motorway are generally towards spots where I'll need the off road capabilities. Off climbing in Portugal next spring for example and greenlaning in Scotland
I have a 110 200TDI 92, and no issues on motorways, happily trot along at 60 or so , not much desire for more tbh. We have driven France, Spain, Poland, Germany, Austria, Switzerland, Italy to name but a handful. When we did Corsica we booted it down to South of France on the peages.....

This is a 200TDI...

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Don't consider a 1.2 unless you live in Norfolk (Pancake flat). I've got a 1.2 in my Defender from the previous owner (North Bristol = flat). I live in the Clwyd range in Wales (hill country). a completely useless T box for this environment. The distance between 3rd and 4th is what makes it unusable. 3rd is too low and 4th is too high.
Currently putting it back to stock.

dag019 and Anaconda live in the Thames valley and Warwick. Both flatlands compared to Wales. A 1.2 would probably be fine there.
 
I've tried different transfer boxes in my 200tdi 90
If using a 1.2 box then fit lower profile Disco tyres or it'll be very high geared and work very hard on hills and when towing.
With Wolf wheels I found the standard 90 box the best overall
If you want to cruise at 70 plus then an old Land Rover isn't the best vehicle for the job
 
Is a 300tdi any more powerful?
Not really, 107bhp for a Defender 200Tdi and 111 in a Disco. claimed to be down to the different intake manifold. But I bet nobody can tell this from the drivers seat. 300Tdi is also 111bhp. And same torque as the 200Tdi Disco. The 300 is really just a "productionised" version of the 200Tdi that makes it cheaper to produce.
Forgot to mention my son's has a 1.2 transfer box and I also agree it is fine for all his driving. I would say the longer gear on 1st is beneficial. My Td5 1st gear is almost a waste of time, as soon as you are moving it's then straight into 2nd.
1.2 is arguably a bit tall, but also depends on the gearbox gearing as that also changed over the time.

A Disco has small tyres and taller transfer high range. But is geared quite similar to a Defender when you consider the Defender is generally on taller tyres.

If you tow a lot, 1st high will need you to slip it if you have the latter gearbox gearing and a 1.2

It also won't really pull 30mph in 4th very well and you'll need to be over 50mph to properly use 5th. For cruising you'll need to have more than stock power to main speed on hills.

This is my somewhat modified 200Tdi with Disco LT-77 and 1.2 transfer box.
 

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