Offroad-Express

The water temperature gauge in my Hilux was stuffed. When I start up, the factory gauge goes to halfway straight away and doesn't move from there even with a radiator clogged with firewood loop mud on a long hill climb. It even did this when I disconnected the wire from the sender unit. I bought a cheapie gauge from repco that measures in farenheit (it came with a new sender unit also). I've wired up the new gauge with the existing electric sender unit (used a new power and earth and the existing sender wire). It now heats up at the speed you would expect it to on the gauge but after about 5 mins driving will sit at 250 degrees faranheit (also the max on the gauge) which is about 120 celsius. So I figured this is just that the new gauge isn't calibrated to the factory sender unit, I took the old sender unit out but the new one is imperial thread so won't go in to the hilux. What do you guys think is wrong with this? Are all sender units the same? So will work with any gauge? Or have I made a mistake with my wiring?

you need to use the sender that came with gauge .you can get adapters for the thread

or put the guage sender in another position eg radiator, or near the thermostat etc

I went to blackwood paykels for an adaptor. they had heaps when i was there, so i'm sure you'll find the right one