whiskey52

I have an '81 911 with the oil temp guage that just shows the bars (no numbers) part # 31027485,5. and just purchased a guage from an earlier year with numbers, part#31027485,7. the back of the guages are identical but the new guage does not register any change. I have the brown wires set to the top post, the red/white wires set to the inside post and the green wire set to the outside post (as yhou look at the back of the guage).
what am I doing wrong? do I have it wired incorrectly or is there a different sender I need on the engine block?
thanks

porsche930dude

yup you need the correct sender.

DRACO A5OG

Just FYI, if you look further to the side of the OEM guage, there are numbers.

+1 on correct sender

Edgy01

It can be quite difficult to install the sender without dropping the engine. (I did one of mine when the engine was out for rebuild).

porsche930dude

My sender was directly accessable to right of the fan above the chain covers. There is another one in the bak but i think its for the computer. I could be wrong but when i switched out my guage thats the sender i switched and it works fine.

I have a 69-76 sender i will sell you its part# 901 641 632 00 . I dont know if thats the one you need

old man neri

That one is for the warning light.

porsche930dude

a temperature warning light? I wonder what temp it kicks on at?