Defender TD to Discovery 200TDi engine conversion

Well for the last couple of months I've been busy doing an engine conversion. This was something I was considering anyway but after my TD engine died completely (siezed, suspected cracked head/block etc) the decision was made for me!

Below is a complete guide of how I did it and I've created a PDF file of the process that includes some pictures too. Hopefully this will help other people out thinking of doing the same.

You can download the PDF version at http://www.appware.co.uk/static/landy/200tdiconversion.pdf

Cheers

Richard


Land Rover 90 TD to Discovery 200TDi Engine Conversion

Parts Required

* Land Rover 90 TD
* MOT failure Land Rover Discovery 200TDi
* Disco conversion downpipe
* Disco conversion intercooler pipes
* Extended 200TDi oil cooler pipes
* New rear crank oil seal
* New clutch (clutch and release bearing)
* New heavy duty clutch arm
* New alternator and power steering belt
* New filters and gaskets

Conversion Process

Work to do to 90

* Disconnect battery and remove
* Remove bonnet
* Disconnect bonnet stay, bonnet then lifts all the way back and can be lifted off hinges
* Remove front bumper, grille, and front centre panel
* Drain coolant
* Disconnect bottom radiator hose and drain all coolant
* Remove air cleaner assembly, fan, fan cowl, and radiator
* Remove turbo heat shield and loosen exhaust downpipe at first connection
* Remove heater hoses and control cables from clips on rocker cover
* Remove breather pipes from rear lifting bracket
* Disconnect fuel pipe connections - remove fuel feed to injection pump, spill return from no 4 injector, fuel feed to lift pump, lift pump to fuel filter
* Disconnect throttle cable and remove
* Disconnect power steering hoses
* Disconnect brake servo vacuum hose from vacuum pump
* Remove engine wiring harness
* Disconnect heater plug harness from heater plug number 4
* Support engine with engine crane
* Remove engine earth strap
* Undo engine mounting rubbers top and bottom
* Raise engine, remove rubbers, lower back onto chassis mountings
* Remove starter and harness
* Remove all bell housing fixings
* Lift out engine
* Remove fuel filter from bulkhead but keep fixings

Work to do to Discovery

* Disconnect battery
* Remove bonnet
* Remove engine wiring harness from bulkhead
* Remove radiator assembly
* Disconnect cyclone hose from air cleaner hose
* Remove air cleaner hose from turbo
* Remove feed pipe/hose from turbo and intercooler
* Disconnect heater hoses from cylinder head and heater rails
* Remove bolt attaching breather pipe clip to cylinder head and move breather pipes aside
* Disconnect hoses from power steering pump
* Disconnect bypass hose from thermostat housing
* Release bypass hose from retaining clips on front timing cover
* Remove throttle cable from injector pump
* Disconnect feed pipe and spill return pipe from injector pump
* Disconnect both pipes from fuel lift pump
* Disconnect servo hose from vacuum pump
* Loosen exhaust downpipe at first connection
* Remove oil cooler pipes from oil filter adapter
* Disconnect ground strap from starter motor
* Support engine with engine crane
* Remove engine mount bolts
* Remove all bell housing fixings
* Lift out engine (I withdrew from front by angle grinding the front centre panel out of the Discovery)


Work To Do to 200TDi While Removed

* Remove flywheel cover and fit old TD flywheel cover. This avoids having to cut and retap studs in different positions
* Change the rear crank oil seal if any signs of leaks. Only use a genuine Land Rover one as its much better quality than the others
* Fit a new clutch. I found that one of the small spark plug spanners is perfect as a clutch alignment tool
* Fit new oil filter
* Replace rocker cover and sump gaskets


Work To Do to 90

* Fit a new clutch release bearing
* Fit a heavy duty clutch arm
* Remove exhaust front section
* Move clutch pipe mount from corner of bulkhead 6 inches across to the right
* Clean up engine bay and protect exposed chassis areas while you have easy access
* Cut down bottom radiator mount brackets by 3cm - Angle grind tops off, cut 3cm from height, reweld tops back on
* Hoist engine into position
* Line up bellhousing studs and attach all fixings. You may need to adjust angle to do this which can be done by an adjustable engine lifting bracket. I did it by jacking up the gearbox end
* Connect starter motor wires and connect earth lead to chassis
* Connect exhaust heat shield
* Fit engine mount rubbers
* Prepare to fit TD loom onto engine by noting colours of wires and positions of 200TDi loom.
* Remove 200TDi loom and secure TD loom to engine. All the colours are the same so connect as the 200TDi loom was. The only change is to the alternator where you cut off the connector block and use spade terminals instead; the thin white wire is no longer used
* Attach and adjust the Discovery throttle cable
* Fit the intercooler top and bottom pipes to the engine
* Fit the extended oil cooler pipes. I secured mine with a bracket as they were longer than anticipated
* Fit the internal heater pipes (steel pipe feeds rear, pipe nipple feeds front) using the old ones from the Discovery
* Fit a new temperature sensor to match the TD gauge. Depending on your old TD engine the sensor from that may fit but there are two different types so not always. Mine didn't so the temperature gauge reads just under red when it should actually be in the centre
* Fit the power steering pipes. I used the low pressure one from the TD and the high pressure one from the Discovery. The TD one still fits the bracket on the rear of the crossmember but the Discovery one is the wrong shape so you need to make a bracket to secure it to the chassis rail
* I left the header tank from the TD and used the TD radiator pipe. The bottom engine connection is slightly kinked so adjust as best you can. The smaller pipe from it that goes to the header tank needs to be extended so I used part of the old Discovery pipework and a piece of standard copper heating pipe to join the two with small jubilee clips
* Fit top radiator water pipe. I used a cut down pipe from the Discovery for this
* Fit the 200TDi fuel filter to the bulkhead (this system is simpler than the TD). You will need to extend the existing fuel hoses with 8mm id (internal diameter) fuel pipe and small jubilee clips
* Fill the PAS header tank
* Fill the water tank
* Check the oil level of engine and fill correctly (especially if you drained it all out earlier!)
* Prime the fuel system with the hand pump on the lift pump.
* Disconnect the fuel solenoid wire temporarily
* Reconnect the battery
* Turn the engine over with the ignition key which should prime the fuel and oil systems.
* Reconnect the fuel solenoid wire
* Turn the engine over with the key and this time it should fire up if all is correct!
* Check for any leaks anywhere or strange noises!
* Let the engine run up to temperature and double check for leaks again
* Mount and fit the exhaust to the downpipe
* Use the old TD air filter system and using a combination of pipes from the TD and Discovery you can just get it all to fit together
* Test that the clutch and transmission is all working. You will probably need to bleed the clutch which will have lost fluid when fitting the new clutch arm
* Refit bonnet, bumper etc
* Test drive and make any necessary minor tweaks!


CONVERSION DONE :)

Post Conversion Tweaks

* I found the turbo whistle was louder than expected. This turned out to be the top turbo hose that needed tightening up.
* Although acceleration was much improved I still found the engine lacking at the top end. This turned out to be the accelerator cable needing adjustment (in the cab) as it was only opening to about 75% of full throttle.
* After a week or so the alternator and power steering belts needed adjusting again as the new ones had slightly stretched once bedded in.

Other Information

This was the first time I’ve ever changed an engine never mind doing a conversion from one engine type to another. I’m no mechanic by any stretch of the imagination but with a half decent collection of tools, a double garage to work in, and lots of advice I managed ok so I reckon most other people could. It was a great learning experience too so I highly recommend it!

I approached the job logically and did LOTS of reading up on the web and asked advice when needed on www.landyzone.co.uk which was invaluable. I loosely based my conversion on the excellent thread by Patman on Landyzone.