Flea- i just went through the same... idk if you mean pass side when you say rh side but my problem was on the drivers side... i just got it sorted... I THINK... check out these threads for a video of the noise and pictures of what caused it for me

https://landroverforums.com/forum/di...exhaust-46564/

https://landroverforums.com/forum/di...onfused-46784/

 

What does that involve?

 

Remove oil pressure switch near oil filter passenger side. Screw in 1/2 X 20 thread adapter to whatever thread your oil pressure gauge needs (blister pack aisle at parts store). Buy or rent oil PSI gauge.

Crank truck. Cold, the oil PSI should go high, and be high for both idle and revved up, because oil filter is bypassed and thick cold oil is getting all the pressure the pump can give. When warmed up, the pressure when revved up will be about the same, perhaps a little less. The pressure at idle will drop as oil thins out from warming up, spec is 50 PSI for revved up, and above 10 PSI at idle. On a D1 the spec is lower, only 30-40 when revvd up. Mine did 44-45 when cranked cold, settled back to 42 hot when revved up, and 22-24 at warm idle.

A cracked oil pump can tick (not always), will pump at some kind of pressure (enough to turn out the light which comes on at like 7 PSI), but usually does not pump enough at speeds.

Also see tech section for https://landroverforums.com/forum/di...estions-46975/ which shows a jumbo oil filter with low internal flow restriction.

 

I have the same type of ticking, sounded louder under the engine but with sthetoscope it is clearly commimg from under the driver side valve cover. I usually hear it when I get to work, around 25 minute drive, no ticking after short trips like 3-4 miles even when the water temp is at the midline.
Local Harbor Freight was out of the pressure testers. Will check with them again in the next few days.
I also have loud knoking at start up followed by some metalic short squicking, which goes away after 1-2 minutes and I previously used seafoam and found that the manifold to pipe gasket was leaking, which is most likely causing the sound.
If my oil pressure is ok, I will just do the good maintenance as recommended here and drive the car for as long as it drives.