Nissan Patrol 4x4 (Africa)

I don't want to hijack this thread, but maybe someone can assist me....

I have an extra oil cooler that was fitted by the previous owner. The oil enters a pipe ( grey one on the photo) from the adapter plate between the filter and the engine, closest to the cab. This grey pipe then runs forward to a metal thingy as seen on the photo, and continues forward to the oil cooler and then returns back to the metal thingy and back to the adapter plate on the engine. Now my question..... what the heck is that metal thingy for, and what does it do? When I had it disconnected a while back to clean out the system, it looked like it is supposed to be a bypass or something of the sorts. However, the hot oil can flow in any direction. there was nothing that I could see in there that would prevent the oil just going straight back into the engine. I never thought anything of it until now.

Hi Cedric,

Could be a check valve that only allows to oil to flow in one direction.

yeah I thought that too, but if you blow or suck on any of the tubes ( when clean ) there is no restriction in any direction, so was just wondering if it is a type of check valve that someone has possibly removed the inner workings for some reason. There is a circlip on the top that can be removed, but I haven't tried that yet as with my luck, there is a ping-gone inside........ ping .... and then its gone .... never to be found again...... hmmmm maybe that's what has happened previously and thats why it doesn't work like a check valve...... hahaha