fzrtim wrote:I had this problem on my conversion. I seem to think the 4jh plug for the neutral and oil sender are the opposite colours. Simply swap them, the plugs are the same!

Just had a look at mine and remembered why i had problems with mine. The oil/neutral plug is green on the 600 motor and dark red on the 3tj. I had problems because i confused the plug with the fuel sender which on the 3tj is green. So make sure the oil/ neutral switch are pluged into the red plug.
Failing that the oil sender could be faulty.