You mean how the sender works? ... Im no engineer but I ass-u-me there is a tiny dwarf inside the sender who reads it of a tiny oil pressure gauge and then proceeds via morsecode send the readings to another dwarf inside the gauge itself who in turn rotates the indicator.
yea, that's it.
Yeah, alright...l walked in to that one!
No, what l meant was how does simply bolting the sender on the top of the housing get any readings? l cant see how it would work like that! lts not like you're pluging it in to something...