hi all I bought this wonderful oily engine off ebay a few months ago and are just getting around to doing something with it after trying to work out what it exactly is im a little confused as all the landrover engine numbers are different to the one I have the number on my block is 10A20623 any help on a bit of info would be brill

 

I don't know about numbers, but...Is there an upper intake plenum on it? If there is a upper aluminum intake with black and silver with the numbers 4.0 or 4.6 in approx. 3" numerals, its a gems motor(if its all silver and has a 3.9 on it its a "14CUX"). If the intake looks like sections of tubing it's a bosch motor.

Thats all I got...

 

Here's a basic overview of clues.

Look at the engine pan (sump) is it alum or steel
Alum will certainty be a Bosch engine.

Steel pan
Most likely Gems engine either for P38 or Discovery1
Does the pan have a side mount 32mm drain plug D1
Slim line metal pressed pan with wave form down the flanks P38 centre drain plug

Now remove the pan look at the crank web at #1 & 2 sections of the crank.
Observe 4,00 0r 4,6 cast into it.

For info D1 had side oil pick up, P38 had a pick up attached to the timing case al la Bosch engine.
If you see nothing then suspect 3.9 4.2 build--the crankshaft might tell you with casual observance, later engines of this genre had 3.9 and 4.2 on them

Now for mongrel builds --look to see if the crank sensor mount plate has been changed. Is there some small alum plug inserts in the block flange where the pan meets block?
Definite early CUX14 or Gems engine if you observe these

If the cam is still in it is there with a skew gear on it?
Early CUX 14 3.9/ 4,2 engine "con distrib"!

Going back to the cam sprocket Gems engine had simple segments in it, Bosch engine had a distinctive L shaped slot for cam sensor excitement.
With all that under you belt you should be able to firm up what you have Senor Sherlock!
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