300Di Conversion Into My Series 3 Hybrid

I've been giving the Hybrid a serious thought as of late, what motor should be in it considering it will be tax free next year (2010). I'm happy with the performance of the 2.25L engine, but the economy is the killer, so therefore I've decided to convert my hybrid to a 300Di powered vehicle.
A deal was done, I now have a 1998 defender 300Tdi motor with only 170000km for my hybrid.  


I've done a lot of research on the internet, information for installing a 300tdi into a series Land Rover is unfortunately hard to come by but this conversion has been done. But up till now there has been no 300Di conversions.
The removal of the turbo will give a hp rating in the region of approx 85ish, but still a very healthy 170 to 180 ft-lb of torque that comes on much sooner in the rpm range. All figures that are well within the range that the 2.25L  gasoline engine gave me.
 Another thing that is sticking in the back of my mind and ultimately will steer this conversion is with any motor conversion here in Sweden, is the fact that the new motor no mater the type of fuel, it's power outputs can not exceed 10% of original manufacture figures.



 The first order of business is how to match up the motor to the series 3 transmission? If you listen to the hear say found on many of the Land Rover forums, they will tell you that you will need a 2.5Td fly wheel housing. Therefore I followed the internet wisdom and bought the said fly wheel housing and sat here waiting for a prominate Lr forum user to send me it. After many months of waiting I finally realized that he would never send it.

So I decided to "try it out for fit" a 300Tdi fly wheel housing from a spares motor on the series 3 transmission. To my complete amazement it fit like a glove. So the myth of needing a 2.5Td fly wheel housing for matching up a 300Tdi motor to a series 3 transmission is total rubbish. With this combination I used a new series 3 clutch and pressure plate.

By removing 3 studs at the bottom and one on the right, the fly wheel housing fit perfectly snug with the transmission, loosing 4 of the 12 mounting studs is not good though. Looking at the bottom of the fly wheel housing there are 2 unused blanks for studs. Matching these up with the series transmission I drilled out the outer lip of the bell housing. Then I tapped the blanks and reused 2 of the removed fly wheel housing studs. At the end of the day I have 10 studs of the original 12 to secure the two units together.



 With everything together I lifted the motor and transmission into place for a trial fit. The first thing that was apparent, is the strengthening brackets that are built into the fly wheel housing are coming into contact with the transmission cross member. After a lot of head scratching I decided that the best solution would be that I removed the strengthening brackets. Later on I will find that this was the best decision as the bracket on the right hand side was too close to the front propshaft.




By using the transfer case mounts as a my base reference points I was able to move onto creating motor mounts. First of all, the right hand side series motor mount has to removed from the frame. The left hand side mount is small enough that it can stay. It poses no clearance problems for alternator or the exhaust downpipe, therefore I say no need to cut anymore from the galvanized frame.

Loosely based on the motor mounts in a Discovery, a little bit thicker plate (5mm) was used. The first thing I've noticed on both the Disco and a Defender that I was looking at, the plate that the motor mounts sit on, it's as if they are sitting in a cradle. The ends are formed for the rubber mounts to sit up against. So the first thing on order was to mimic that bend.

From there I aligned the motor where I want it and began with the side plates for each side.  Doing this, I had to keep in mind that the bolt holes for the bulkhead uprights were still accessible. Only one plate had to have a recess cut into it, so that a nut and washer will fit later.

Once I had made the motor mounts I again installed the motor and transmission, fixing the transfer case mounts so that I can adjust the motor to the correct height and alignment before locating the motor mounts to their final position. A few spot welds and out came the motor for final welding.



With the engine finally installed all the "little things" needed to be addressed before the hybrid can be driven.

 The first thing that was apparent is the vacuum pump on the motor, it had less than 1 cm clearance with the throttle linkage. To solve this I decided to remove and scrap the series throttle linkage and installed a Defender accelerator pedal. From there I installed a Discovery RHD throttle cable. The mounting plate for the Defender accelerator pedal had to be spaced a bit from the firewall and the arm portion of the pedal needed about 15mm of metal removed from the bottom portion so that I can get full throttle movement at the pedal and at the injector pump.
One of the pluses with going with the Defender accelerator pedal is that I removed the entire rod system for the original throttle linkage. This in turn gave me a full 25mm clearance at the vacuum pump and the firewall.

Then from there I plumbed in the brake vacuum pump on the motor. With the servo more forward than the pump, I was unable to simply run a hose and be done with it. A 10mm copper fuel line had to be formed into shape so that the two components can be connected to each other. Overall a tidy job and should work perfectly fine.

Next came the fuel tank, my tank had to be purged of the old gas so that I can reuse it for diesel. Also a fuel return pipe had to be installed.
















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