Sadly, I'm thinking of converting to Tdi. Please help.

Hello folks.

As some of you may know I have a 3.5 v8 disco. I thoroughly love the engine, it runs very well, has been reliable, is waterproofed and drives/sounds wonderful.

However, I have been talking with my old man about setting up our own biodiesel production rig, to combat the crippling price of fuel. It usually costs me between 150 and 200 quid for a 2 day green laning weekend.

With the biodiesel this would be a thing of the past.

It saddens me to have to consider it but needs must I think.

So:

I don't know anything about diesels tbh. Not more than the basics anyway.

I know that the cheapest way probably is to buy a Tdi disco, and scrap the body.

My disco is a 200 shape, i have a very good chassis and fully repaired body which I want to keep.

Firstly, what do you think is my better choice please? 200 or 300 engine/gearbox?

Second, I know that you can cut the mounts off and change them, but that seems like a bit of a tricky job to get right. Looking under my dads 300tdi I can see that the gearbox crossmember mounts are very different to mine.

I did think it might be easier/safer to pull the body off mine and drop it onto the 300 chassis, and then swap my axles onto it.

I realise there is a lot more work in rebuilding the whole car than simply fitting a few mounts, but this being my first time I don't want to end up getting the mounts wrong or not strongly welded etc.

Would a 200tdi swap require less awkward welding than a 300tdi?

Obviously it's much easier to swap axles/suspension etc etc when the body is off so I'm not against the idea as such - my concern is how much I need to do if I use my existing chassis.

All help/ideas appreciated,

Cheers guys

id go 200 tdi mount fastening isnt difficult 200 lt77 is a good strong box i dont think youd gain anything with r380 as it would want rebuild,although both 77 and r380 can use the same mounts either cross member,2 seperate chassis mounts or 5the underneath mount .if you mount gearbox etc fit engine without clutch with a couple of bolts you can easy lift to fit and tack mounts in the correct position ,then remove/refit after welding properly,which only needs to be across the top and down two outer side

I reckon the 200 is a stronger engine,if a bit agricultural

ok guys thanks for the advice so far, jamesmartin as usual your knowledge is invaluable!

tbh im pleased that the 200 is favoured so far, seeing as mine is 200 shape.

is 200tdi tuneable? a major deciding factor is that i want to be able to uprate the diesel to provide a good power like im used to with the v8 (im not looking for miracles, just uprated torque through the midrange)

also james, i just spent £300 last year having my v8 lt77 reconditioned with new 1st and second syncros, new reverse gear and selector forks, as such it is now a nice gearbox to use. can i use this to mount to a 200tdi motor or is it simpler to fit new gearbox (often the lt77 is needing recon aswell though i think)

i have looked a little more this afternoon, i think body off is more work than i need so probably just fit engine mounts as above.

can mounts be bought new or need to be cut off other chassis?

thanks for the help so far!

another thing:

james, are you saying that i could mount a tdi unit using the two existing mounts on my transfer case and swap the two engine mounts for my v8 to fit the tdi block.

the v8 is mounted like this so i suppose the tdi would be same

this would make it easier like you say because all i have to do is level up and line up the engine block mounts.

i can measure this off my dads 300 tdi which would be handy.

hmmm, sounds ok

need to know about the engines really folks: research says that a 200tdi prefers biodiesel, but a 300tdi prefers tuning.

anyone able to comment?

thanks again!

200tdi can be made a very pokey engine , ive got turnd the pump up on mine and its very surprising how much torqe it has got ,

atb tim

as for bio fuel , ive just started on runing mine on shop brought veg oil with a little bit of diesel mixd in , veg oil at tescos is £1 a litre

My 300 tdi runs on homemade bio period-never been to a garage in the 3 yrs I have owned it.Costs around 12p-15p litre (inc electricity)if you can source your waste oil for free

'ello

Ok thanks mate, good to hear a 300 is happy on 100% bio.

Tbh I am swinging towards a 300 for a few reasons, despite what people have said above. See what you think:

All the challenge guys use 300 (or td5)

The 300 was accepted by the army whereas the 200 was not (because 200 was harder to do timing belt etc apparently)

The 300 has a twin alternator mount available.

I assume the 300 will respond to tuning because of it's revised head/injection setup



I am concerned that if I buy a 300 disco the output splines on the box will be worn on the r380 and the box will be shot. I would look at using my v8 lt77 if it can be made to fit because it has had a recent rebuild.

Ashcroft always state that the r380 is the dad superior gearbox though. Mine is an LT77S which helps perhaps.

Thanks again guys, as you can see this is giving me a little bit of headache!

Cheers

lt77 is a good box ,r380s have weak synchros and the same main bearings,your lt77 could be fitted by swapping bell housing and using thicker spigot bush ,shaft size v8 19mm diesel 22 mm,or i could swap input shaft and would have spare bell housing 200 is best bet imo,basically same engine but less trouble,all boxes r380 or lt77 will have output spilne and input gear wear if cross drilled gear fitted ,which was really main fault with lt77, never found many with gear damage with reconditioners r380 is favourite as its so much easier to assemble ,200s where available with a/c although some dont have lugs drilled on timing case.so twin alts could be fitted

Thanks for that info James. I thought that diesel clutch plate had different splines to v8 clutch plate? If not then I can easily get a spigot bush machined. I would like to use my gearbox because input and output shaft both have very minimal wear, because v8 is smoother engine it does not wear as much apparently. I also fitted cross drilled input gear when I had the transmission out last year. Bell housing is easy because I plan to buy a complete car so that I have all parts required.

I would naturally say 200 is better because I have seen from experience that the 200 shape disco is better quality metal (the imperial bolts don't shear, the metrics do) and also the 200 is a much simpler car which I like.

Also 200 slave cylinder will fit my imperial pipework, etc etc.

I'm not arsed if it is noisier, I just want it to be powerful enough to be useable.

I will have a look about for a 200tdi, would be really handy if I could drive one tbh, because I have driven my dads 300tdi.

All I really want to know is what you mean by 'same engine with less problems' because I thought that the 300 was designed to clear up the 200 problems and also everyone always says 300 best engine when talking about defenders.

What problems do you get on 300?

Is it like saying that 3.5 is better than 3.9 because basically same engine, drives slightly more lumpy and noisy but is simpler and will run forever whereas 3.9 often gives problems.

If a 200 will tune up nicely and I can fit twin alternators and it won't snap cambelt all time and be difficult to replace then I'd be happy with it!

The first thing i would have before undertaking the swap is a good supply of veg oil for the bio production.

if you have not already, check out the veg/bio forum listed in my sig, all the info you need is there and expect a steep learning curve.

good luck and welcome to the oily side.

i like 300 but how many 200s have problems very few ,ive built hundreds of 300s admittedly usually fault of rad ,but other things are lift pumps ,vac pump,alternator,different mounts,p,gaskets etc,cam belt is only a little harder in that you need to remove water pump and some bolts holding pas pump and alternator bracket ,early v8 splines where 10 spline lt77 all the same v8 or tdi

hifly said:

The first thing i would have before undertaking the swap is a good supply of veg oil for the bio production.

if you have not already, check out the veg/bio forum listed in my sig, all the info you need is there and expect a steep learning curve.

good luck and welcome to the oily side.

Click to expand...

Thanks mate

Yes I have obviously had to look at getting the raw material

I do also think thought that even on pump diesel I can male a saving. The v8 is just TOO thirsty for my current usage.

I have had a look on that forum, Many thanks.

Thanks for even more info Jamesmartin. I still haven t been able to decide 200 or 300.

Going to have a look at an ex-police 300 tomorrow that has supposedly got a 60k engine and box.

Cheers, sam

Sam you have a pm.
the 200 was hugely developed prior to preduction in 88/89 but sadly failed eu noise and emmision tests in 94 so landrover had to develope it to comply hense the 300.
The 300 is known for having overheating / head problems and produce identical power output figures to the 200. the 200 is a stronger engine and as for the cam belt i cant see any issues with failier or replacement.

Mr Noisy said:

Thanks mate

Yes I have obviously had to look at getting the raw material

I do also think thought that even on pump diesel I can male a saving. The v8 is just TOO thirsty for my current usage.

I have had a look on that forum, Many thanks.

Thanks for even more info Jamesmartin. I still haven t been able to decide 200 or 300.

Going to have a look at an ex-police 300 tomorrow that has supposedly got a 60k engine and box.

Cheers, sam

Click to expand...

Hi Sam, I've had both a TDi 200 Disco and a TDi 300. Both worked well but the TDi 200 was at least 15% more economical and had just as much if not more power. The official figures say they are the same.

One important difference between the 2 engines is the location of the water pump. On the 200 it's set low - on the 300 it's set high. As a result there is a chance of the pump not working at it's best on a 300, if the coolant level is anything less than perfick.

Re the noise of both engines to be honest I didn't notice any difference at all.

All the guys round here prefer the 200 in their off-road trucks.

I would say 300 all the way!!
I have just done the V8 to TDI conversion on my 90 so if you need any help let me know.

Reason for 300 is they are more tuneable, more around for spares!
300 is same as 200 but revised (better).
Mine starts on the button without fail.
I have tweaked my pump slightly to give the pull off it deserves.
It has done almost 200,000 miles and rings and turbo are sweet!! (last owner for 11 years was 70 years old). The 200 and 300 had same power because of restrictions on 300 EU rubbish (EGR, CAT, DPD if auto)

hi guys

thanks very much for some very helpful posts there!

still a bit of conflicting advice, but its looking like the 200 is the favourite.

that is a good thing because then i can use my v8 lt77 gearbox which was rebuilt last year and i know it has very good input/output splines.

yes there are more 300s around for spares, but britpart manufacture/source pretty much everything for land rovers so i cant see spares being an issue

it also nice to know that the 200 is more economical. it is also handy that the water hoses will fit my tank and heater etc, the clutch cylinder threads are the same etc, list goes on.

i think its safe to say id be better with a 200, as long as i can tune it enough, and i need to talk to my dad about it (he wants to get a 300 so he can rob some spares for his 300 ) because i STILL havent decided what the best course of action is, although my gut feeling is 200tdi, as most people have said.

argh such a difficult decision!

You have PM back

I thought I better tidy this thread up.

THANKYOU VERY MUCH to everyone who contributed on this topic, but I have now decided to cancel the diesel conversion idea. I really really appreciate everyone offering their ideas/knowledge, but I have done some sums and reckon I could be into £1500 to get the diesel how I want it. That includes buying a car, new intercooler and pipework, new clutch, potential gearbox rebuild etc etc.

My v8 has a new radiator, has a new clutch, has a rebuilt gearbox - it just didn't seem to make sense seeing as I probably wouldn't like it with a diesel in anyway.

The thing that tipped me over the edge was the fact that I don't need the car, I want the car. And I want the car because I like it. And I wouldn't like it so much, if at all, with a diesel motor.

MUCH better as a useable vehicle, I agree, but not for me I'm afraid

Once again, thankyou for the help gents

P.s. Here's the new plan.



Sorry