My tuppence worth for that plug relates to it being used for the tow bar connection for trailers with electric braking, which are popular in the USA.

My understanding of ENV which I got from an old engineer friend of mine was that there was a collaboration between Eaton, Nuffield and Vauxhall back in the 60's making strong axles for light commercials, much like Dana did with theirs. These axles were available to all manufacturers and were...

Your pump could be full of air. You could try unscrewing the oil pressure sender and drilling slowly on the pump.

I drove an MGB V8 fitted with a downdraft two barrel Weber from a 3 litre Capri, which was a lovely mod for a lighter road car.

Twin HIF44 SU's and their manifold from a Rover SD1 will fit straight onto a 3.9. These carbs are good for over 180 BHP and give good torque and smooth throttle response lower down in revs, especially off roading in a Land/Range Rover. I'd suggest staying away from the Stromberg carbs from a...

Scrub/wire brush off all of the rust from the bolts. Apply a few drops of diesel to them on both sides of the axle flange. It's the best penetrating oil in my experience.

What is your fuel level when these problems happen? The bottom of suction pipe in the tank can rot away, hidden behind the mesh pre filter. Does it have this problem on a "full tank"? It sounds like a fuel supply issue, either flow or pressure.

There is a way to make your leaf springs perform in a more civilised way. Rover used this techique on their P4/P5 back in the day. The springs are greased thoroughly between the leaves and then fitted with leather gaiters to keep the water and road dirt out. I have done it once where a friend...

I'd suggest taking off the multi plug connector and checking the cleanliness of the terminals. Also check that they look like they can get a bite on the male terminals on the motor. These multiplugs are not a convincing fit into the wiper motor at the best of times.

I'd guess the top of the rad is well below the height of the thermostat housing. Make sure the coolant level in your header tank is higher than the thermostat, otherwise it won't bleed properly. If you dont have a proper header tank, search online for pics of TVR Chimaera 400 engine bay. That...

Is the engine idling at the correct speed? If the idle is too high it will amplify any "slop" in the drivetrain when you select gear. Does it make the bang if you select D or R with the hand brake on? With hand brake on, youre removing sny slop in the props and axles.

If you're in a 109, the Salisbury rear axle will save you due to having big diameter shafts. Try it in any SWB and there will be lessons learned...

I can't offer any further assistance to your interesting view on the law of physics.

I'd advise not to pull the hand brake whilst in motion on dry tarmac. It's easy to snap a rear shaft or punch the rear diff pin out through the axle casing. I'e seen this several times. Easier to do on Series 3 with the much longer hand brake lever.

A Series gearbox will handle a V8 when treated with mechanical sympathy but I'd fear that the torque of a TD5 at a lower rpm/shaft speed might be too much...

Your timing chain has stretched. Advancing the pump on its mounts can help but is not perfect as your ECU ultimately controls pump timing. You can also search online for P38 hot start kit, which is basically a small resistor in a box which fools the engine's ECU into thinking you're on the North...

It fools the sender into working in the opposite way.

Bend the arm at the sender end 180 degrees and bolt it back into the tank " the other way round". I've done this before. You can solder on some extra material if you can find an old wire coat hanger.

To the best of my knowledge, Land Rover speedo drive gears in Series 2/3 vehicles are the same. The only difference in speedos was between SWB and LWB models as they came with different sized tyres. A LWB speedo was around 11% undergeared due to being fitted with the larger 7.50's. If you look...

I'd second the base idle adjustment. If the ECU doesn't see the correct resistance/voltage signal from the closed throttle position sensor, it doesn't know that you are commanding "idling". Therefore it won't take over idle control automatically. Idle valves can be sticky but as far as I know...