ENGINE DOWNSIZING ON A SERIES IIII
I have a 1974 Series III with the 2.6-litre six-cylinder engine. It’s a thirsty beast, but I’m thinking of replacing it with a good spare 2.25-litre four-cylinder petrol engine, which should be more economical being smaller and lighter. The steering should be lighter, too. Is this a straight forward swap? Is there a conversion kit to fit this engine? Mark Ward
Yes, the four-cylinder engine should be more economical, but you may be only moving up from around 20 mpg to 24 mpg on a good day. Depending on the amount of driving you do in the SIII, this may not be worth the work involved.
Usually a six-cylinder engine is super-smooth compared with a four. But in Land Rover’s case, the four-cylinder is amazingly quiet and smooth running, so you would not lose much in that respect. You would lose the rather sweet exhaust note of the six but, the most important point here is that the six-cylinder versions are becoming quite rare and they are of particular interest. It would be a shame to lose one by dropping a four-cylinder engine in where it doesn’t belong.
However, the conversion is quite possible, though it’s a bit involved. This centres around the fact that the gearbox on your vehicle is positioned further back in the chassis, so the mountings would need to be modified to the four-cylinder position. Consequently, the floor is different and the front propshaft is longer, and the rear shorter, than the four-cylinder versions. The bulkhead will also need modification in the centre if it is the original 1974 type (later bulkheads had a removable centre panel that could be swapped for the correct type). Ideally, you would need the four-cylinder radiator. I’m not aware of any current conversion kit for this job.
The engine change will have little effect on the steering, if you’re concerned the steering is heavy that is. Assuming normal size, correctly inflated tyres, it’s worth first disconnecting the steering rods from the relay and swivel housings and, with the chassis supported, check they are free (swivels may have been over-shimmed). While they are disconnected, check the movement in the steering box on the bulkhead. It may only need adjustment. Ed Evans