SO - I sell a lot of engine kits to do conversions into Defender 90 and 110s, and often get asked a lot of questions about the conversion and installation process itself. I recently brought in a 1988 Defender 110 from a customer who wants a 300tdi / R380 5-speed conversion, and he gave me permission to take pictures and post a 'diary' here in the hopes that it may help you decide if you want to attempt to do this conversion yourself or hire a professional to do the job for you. If you DO decide to tackle the job yourself (Really not too difficult!) I hope this may provide some help/ instruction or reference material.
** OH! This truck has only 52K miles on it, and I just put new glow plugs in this engine and it runs perfectly! Would be a great upgrade for your Series 2, 2A, or 3 88", 109, or Defender 90 or 110 - Let me know if you are interested in this 2.5 turbo diesel engine, it is for sale ** 503-810-4713
You can always call me at 503-810-4713 if you have any questions during your own conversion.
This job will be the same as it would be replacing any Land Rover 4-cylinder gas or diesel engine and going to 300tdi. Will be almost exactly the same going from V8 to 300tdi, too.
Here is the truck as it arrived to my shop, stock with the early 2.5 turbo diesel engine :
So, the first thing you need to do is to disconnect the battery and remove the hood (or bonnet, if you are pretending to be British). While my hands are still not covered in grease, I like to remove the front floor mats, carpet and floor panels. Remove the screws securing the transmission 'hump' cover to the floor. It may be a good idea to take some pictures while you are doing this, things that seem obvious (Do the floor panes go OVER the transmission hump, or does the transmission hump secure to the floor panels??) you may forget after a few days or weeks.
Sometimes, whoever last put the floor boards and hump in may have used silicone or some other sealant/ liquid fastener. If this is the case, you will probably be frustrated as you bend the shit out of everything as you pull it out. Do not worry, as if going to R380, you were not going to re-use these panels anyway. If you are staying with the LT77, this stuff is aluminum and can be bent back in shape easily enough, and new or good used panels are VERY CHEAP.
Basically, you want to get access to the back of the engine from inside the truck. If you are converting to a R380 5-speed, you are going to have to take out the floor panels and seat box anyway, so get it all out of the way now.
Next, I go back into the engine bay and drain the engine of oil. Remove the lower radiator hose and drain the coolant system. Catch your coolant if you want to use it again!
This particular truck has a Kenlowe electric fan set up. If it did not, the first thing I would have done would have been to remove the cooling fan from the water pump (remember - it has reverse threads!) and remove the plastic radiator shroud, too.
Remove hoses from engine to radiator. Disconnect heater. Disconnect throttle cable. Remove oil lines going to oil cooler in radiator and remove radiator. Unplug wiring harness at bulkhead (Single plug) disconnect battery cable from starter. Disconnect fuel lines from fuel pump on engine. Basically, disconnect everything you can find connecting engine to chassis and vehicle.
From inside the truck, I remove all but two of the 17mm nuts holding the transmission bellhousing to the engine. I place a thick piece of wood underneath the gearbox, on top of the cross member, so when the engine is removed, the gearbox will be supported.
Working back in front on the engine, I remove the nuts holding motor mounts to frame, and remove the exhaust pipe section that attaches to the downpipe, just under the engine. It will be advantageous to you if you can remove the entire downpipe from turbo that then heads down and back, but it is often stuck to the turbo , where the pipe is sleeved on. It is nice to remove this as it makes removing the battery cable from the starter motor much easier, but if it does not come off easily, do not work too hard trying, or damage anything with your 'bar of persuasion' - While you are there, remove said cable from starter, and try to reach in back and remove clamp holding gearbox breather pipes to the back of the engine. This are often overlooked, and they will hold you back once you are trying to lift engine away!
It is about this time I secure a lifting strap to the provided lift hoops on the cylinder head and bring the forklift over. I know not all of you can be so fortunate to have a forklift - AND I AM NOT BRAGGING HERE - but it makes these jobs easier. This is the time you would hook up your engine hoist, and begin to take the weight off the front of the engine. I lift until the weight is taken off the motor mounts, then with a pry bar (If a nudge or two on the valve cover with my hand does not do it) pop one motor mount off it's chassis mount. The other will come off easily now.
Now I go back inside the truck, and remove the last 2 17mm bellhousing nuts , and then come back around to the front of the engine and tug ever so gently towards the front on the timing cover/ water pump, ...and.... OILA! The engine should slide forward and off of the gearbox input shaft. Now is the time to look around behind the engine and make sure nothing is still connected, like the glow plug lead from the ignition switch? Gearbox breathers? Engine ground strap? Make sure all is clear, and then it is just a simple job of lifting up, UP, and UP - There is plenty of room in the engine bay of these things when dealing with the 4-cylinder engine - and once you are high enough and clear of the front cowl/ grille - back on up and remove that powerplant!
Next, the transmission needs to come out. I will remove it out the bottom, so the next thing I do is remove the drive shafts from both transmission and axles (If they have not been removed already) , and then remove the cross-member directly underneath the transmission.
I take the shift sticks off the trans from inside the truck, and also remove the transfer case remote shift housing from the top of the trans. From underneath, I reach around and remove the wires from the reverse switch and CDL warning light switch.
From inside the truck, remove the panel giving access underneath the center seat (or cubby box if you have one) and disconnect the cable going to the parking brake. In the engine bay, remove any clips holding transmission breather pipes to the bulkhead. Remove speedometer cable from transmission. Remove clutch hydraulic line from flexible line going to slave cylinder and be ready to catch the brake fluid that will drip from said line.
At this time, everything should be disconnected from the transmission, and I put a floor jack underneath trans with a block of wood on top, and pump the jack up until it is just lifting the trans. Now I *carefully* remove all the bolts holding the transmission mounts to the chassis, watching to be sure the trans does not start to slip or fall as the bolts are removed from the frame. Once all bolts are removed, the jack can be slowly lowered with the transmission and transfer case supported. If you have someone to help balance from inside the truck, this is nice, but not necessary. Lower all the way to the ground, and if you have room pull out the side of the truck. If you do NOT have enough clearance, you can jack one side of the truck up or the other (with another floor jack) to make enough room to drag the gearboxes out - and that is that. Now time to clean!
The next step I proceed to undertake during this swap is removing the motor mounts from the chassis. The 300Tdi mounts are very different and will weld on in a different location - So break out your plasma cutter (or sawzall, or angle grinder) and cut off both mounts, and then grind all remnants of these mounts down to flush with the frame. I like to make this as smooth as possible, and then clean up all around the grind marks and paint with a rubberized undercoating. Other than being cleaner than all surrounding areas, you will not be able to tell these mounts were ever here.
(TO BE CONTINUED, STAY TUNED....)