29 December 2023
Trevor explains the challenges of engine conversions
Engine conversions in utility Land Rovers have been going on since the days of the earliest Series I models in the late 1940s and 1950s. The prime reason for removing a Land Rover engine and replacing it with a powerplant from another manufacturer is to improve fuel economy (at least in the early days) – taking out a petrol engine and fitting a diesel engine in its place.
Modern day engine swaps are probably more about power and torque gains, rather than seeking better fuel economy, such as the trend for fitting big Cummins truck engines and the currently very popular BMW M57 – a superb straight-six diesel. The popularity of these conversions can be seen in the numerous social media groups and online forums that provide help and support for Land Rover owners who own them, or plan to carry out the conversion.
Trevor's 1983 Defender 130 Tipper
My Land Rover 130 Tipper indirectly falls into the fuel economy category of engine conversion. It utilises a Mazda SL35Ti engine (3.5-litre turbodiesel intercooled direct injection), which had been used to convert a V8 classic Range Rover by Motor & Diesel Engineering Ltd in Lincolnshire. The Range Rover had been converted to dispense with the thirsty petrol V8 engine, for a brand-new diesel engine with decent power and torque, and improved fuel economy.
When the Range Rover had reached the end of its life due to advanced corrosion, the Mazda engine had covered only 30,000 miles – and I was fortunate enough to acquire the complete truck for the sum of £500 (less the cash I got back on spares and weighing in the scrap metal) to fit into my original Defender 130 build (a double cab called Pilgrim).
The (now) tipper Land Rover has this low-mileage 3.5-litre diesel engine under the bonnet, in front of the Range Rover’s ZF automatic gearbox and transfer gearbox. It is a very fine work truck with good power and torque – although no ball of fire when compared with the Cummins and M57 Defenders of this world.
There are downsides to running a Land Rover with a non-standard engine when it comes to parts and servicing – it is no longer a matter of asking for an oil filter from the local Land Rover specialist. No, the part number is required and you may need to visit more than one motor factor to purchase what is needed.
I have had two annoying issues with my 130 tipper. The first was that the temperature gauge was reading high – it appeared that the engine was over-heating, when the temperature was actually normal. This was easily rectified, when I found the ‘round tuit’ (as in, made time to deal with the problem) and found the correct temperature sensor.
I had previously tried a Defender 300Tdi sensor, which did not physically fit. Now, with a Defender 200Tdi temperature sensor on hand, I took the old one out and found the 200Tdi item to be exactly right for the engine.
Trevor’s new fan belt stocks should see him through for a while
The second problem was that I couldn’t get a fan belt to last more than a couple of months before it would start squealing. The adjustment was always correct, yet after a few hundred miles the noise would begin. The belt seemed to stretch. Before long, the limit of adjustment was reached and another belt was needed.
I mentioned the problem to the illustrious Mr Jonathan Culley (who has been running one of these Mazda engines for years) and he pulled the very thing I needed from the toolbox in the back of his 110 – a spare fan belt, which was much more robust than the one I had been using. This thicker belt has been in place for a few months now, with no more squealing.
I duly placed an order for four of these better fan belts online – two spares for me and two for Jonathan.