Range Rover v8 to 200 tdi conversion?

[mt2man]

Any land rover enthusiast on here who know much about converting from 3.5 v8 to 200tdi?

I have a v8 classic range rover and a 200tdi discovery 1 and am planning on making 1 good car out of the 2 and putting the 200tdi in the range rover.

Does anyone know how simple this swap is?

I'm getting conflicting opinions regarding engine mounts etc. Obviously i will be swapping fuel tanks and using the disco as a donor for its loom etc.

Welding isnt a problem, its just nice to know this information before diving in!

Thanks Jack

[composimmonite]

Got Tee shirt as considered converting my Vogue to diesel so looked into what was needed.
Engine mounts on chassis different. Gearbox different (length of input shaft and bellhousing).
As you have a whole Disco as a donor there shouldn't be any serious problems with the conversion.
If V8 is EFi then that has a separate harness for injection so easy to remove it whole and system in demand so resellable.
.

Paul H

[mt2man]

Ah I didn't think about gearbox lengths, would prop shafts need changing?
I have a LPG kit but I'm selling it and the v8 and will be changing to the 200tdi for a few reasons so it's the way I'm planning in going ahead.

I have the whole disco I am breaking so could use everything off the donor, would prop shaft from the disco fit the range rover?

Should have said both are 5 speed manuals, range rover is running SU's. The disco chassis will be scrap so don't mind cutting off the engine mounts etc

Plan on using the entire disco loom as the range rover loom is a mess so wiring isn't too much of a problem.

[optimusprime]

Swap bodies over .......

[composimmonite]

Prop shafts are the same.
The 200TDi engine block is longer than the V8 hence the difference in bellhousing to compensate. (I think I've got the right way round !)
Assuming both gearboxes are LT77 then the important aspect it the output shaft splines. Out of probably 5 Land rover / Range Rover LT77's I had every one had worn splines. Better to sort out now than when worn spline strip at a later date. You might be lucky and the Disco gearbox is sound but if not the LT77 is an easy gearbox to work on so you can "cherry pick" the best output shaft and use that with the 200TDi input shaft. If you have a sound output shaft ensure you use a cross drilled gear to keep it that way. It probably has a plain gear at present as the cross drilled was a very late modification. In fact I have a brand new cross drilled gear and brand new Ashcrofts oil spinner I keep on meaning to put on eBay.




Paul H

[Steve]

Bellhousing for the 200tdi is somewhere close to same length as V8 but totally different bolt pattern, the diesel LT77/R380 has a different spline count and spigot size compared to the V8 versions

[composimmonite]

Oct 19, 2013 12:11:11 GMT Steve said:

Bellhousing for the 200tdi is somewhere close to same length as V8 but totally different bolt pattern, the diesel LT77/R380 has a different spline count and spigot size compared to the V8 versions

DOH !
I think I'm getting confused with the Defender which definatley has shorter bellhousing.

I do know that to fit the gearbox out of my old V8 Vogue to my 200TDi Disco I had to change the bellhousing. At the same time I swopped over the output shaft in the gearbox but can't remember 100% which imput shaft I used. I thought, for some reason, I had to use the 200TDi Disco item in the Range rover box but on reflection that could have been due to difference in splines rather than length. My excuse it was a long time agao and I've had my brain scrambled twice since then

Paul H

[mt2man]

I cant just swap the bodies over.
So its not a case of just swapping engine and gearbox over i need to sort out bellhousings etc? Shafts wont fit because of different splines etc?

I didnt think of that as a problem to be honest, i assumed once the engine was mounted to the chassis all shafts etc would mate up fine to the diesel engine.

[composimmonite]

It'll be an easy conversion. Start with the gearbox and then fit engine to determine where mounts need welding to the chassis. Everything else is then swopping parts over from the Disco.

Paul H

[mt2man]

So I can't keep the gearbox attached to the 200tdi and fit the whole unit as one?

[optimusprime]

Oct 19, 2013 22:57:14 GMT composimmonite said:

It'll be an easy conversion. Start with the gearbox and then fit engine to determine where mounts need welding to the chassis. Everything else is then swopping parts over from the Disco.

Paul H

What Compo said.

I did it the other way round on my landy, ie binned manky diesel, fitted ex RaRo V8. Used same priciple to fit it all in.

Don't forget the Disco is based on Rangie chassis, so the running gear is virtually the same (ignoring ratios and spline differences in some cases)

[mt2man]

I'm not to worried about ratios, just concerned about splines now!

Exactly what problems with splines will I have and won't I be able to overcome this with the parts I have available?

[bavarianretro]

Why bin a smooth, powerful, sonorous V8 petrol for a rattly, smokey, diesel? LPG is surely the way to go?

[composimmonite]

The gearbox bolts to the transfer box. There is then a gear that transmits power from tail end of gearbox down to the transfer box. The gear is starved of oil so wear on the gearbox output shaft is the problem. Imagine removing a drive flange from a gearbox - well that is what you basically have on a Disco / Range Rover LT77. Looks similar to a LDV version of the LT77 but splined slightly different (found out the hard way !)
So use whichever transfer box you want as they rarely wear excessively. Then you need the Disco gearbox and bellhousing. If the splines on the end of the Disco gearbox are worn consider swopping the part with the one from the Range Rover gearbox (will involve stripping down the gearbox but LT77's are one of the easiest to work on).
The gearbox crossmember is detachable so with an engine crane you can lower it to the floor. DON'T try to do it by hand as way too heavy. Even trying to lower on a trolley jack would be dangerous so crane is the only method I'd advise. If you have a sun roof then it might be possible to use a hoist to garage beam, A frame or whatever. Bearing in mind you will need to remove both engines and then reinstall the diesel a crane would be the best option anyway rather than hoist.

Paul h

[optimusprime]

Oct 20, 2013 12:06:44 GMT mt2man said:

I'm not to worried about ratios, just concerned about splines now!

Exactly what problems with splines will I have and won't I be able to overcome this with the parts I have available?

You won't have to worry as you'll be using the gearbox and transfer box from the disco, after all it worked in that ok.

[optimusprime]

Oct 20, 2013 9:55:58 GMT mt2man said:

So I can't keep the gearbox attached to the 200tdi and fit the whole unit as one?

.. its been done .. but it'll be on the heavy side of heavy, and its hard work, esp if you're on your own.
The transfer box and gearbox are heavy enough on their own when they are split ...

My advice, as Compo said, get an engine crane, and make sure its not one of those 500kg capacity ones you can hire, you don't get the lift height needed to clear the front of the truck. ( yes you can drop the front wheels off the car and lower the front end down ... but its a right pain when you need to get underneath to guide everything thru ....)

[mt2man]

I will have use of a 1 ton engine crane so that shouldn't be too much of a worry, the disco has hi and low range and a decent gearbox so will be using that.

Will I have to use the transfer box from the disco or range rover?
The range rover runs on Carbs and has earthing problems with the lights and everything so was planning on using the entire wiring loom from the discovery. So wiring should be relatively easy.

Does anyone know if steering racks are the same on disco 1 and classic range rovers? Also planning on using the PAS steering box from the disco on the range over too

[composimmonite]

Transfer box is the same LT230 for both Disco and RR with LT77 main gearbox. AFAIK Defender LT230 version has different ratios.
There might be some visible differences between steering boxes but are interchangable so no problem using the Disco PAS on the Range Rover.
I notice you say the Disco has hi and low range. That's set alarm bells sounding about the Range Rover. Is it pre 1984 with a 4 speed - maybe with overdrive ? If so then it's got a LT95 gearbox and is superior (bullet proof / no problem with stripped splines) to the 5 speed LT77 so I'd stick with that and use a 200TDi to LT95 adapter.

Paul H

[mt2man]

Ah great cheers.

And the Range Rover is currently a mix match of bits (Tata pickup body fitted) so there's no gaurentee what year gearbox or engine is fitted.

I haven't a clue about model numbers and stuff but;
Disco is 5 speed with hi and low range.
Range Rover has 5 gears not sure if that's 4 speed and overdrive or not?! (No hi or low range)

[composimmonite]

Oct 21, 2013 11:00:33 GMT mt2man said:

Ah great cheers.

And the Range Rover is currently a mix match of bits (Tata pickup body fitted) so there's no gaurentee what year gearbox or engine is fitted.

I haven't a clue about model numbers and stuff but;
Disco is 5 speed with hi and low range.
Range Rover has 5 gears not sure if that's 4 speed and overdrive or not?! (No hi or low range)

Even the 4 speed LT95 had a hi-lo range. The diff lock was vacuum operated. I wonder if when fitting the Tata body the hi-lo range selector was simply not installed ?

If the Range Rover has already been "modified" then, personally, I'd be very tempted to repair or modify the Disco instead as you might find that sorting out a previous owners bodges etc would be more work. Land Rover enthusiasts are used to mix and matching parts but if you aren't in that group and can't even identify what you have then it's going to be harder work swopping parts over to the Tata Range Rover than repairing or building something on the Disco. What about simply putting Tata body on the Disco rolling chassis ?

Paul H