Which sending unit to use?
 

I just got an oil pressure/temp gauge for my 81 Sc. The gauge is from an older 911 and has numerical values for the temp in degrees and pressure in psi. I have the correct sending unit for the temp but I don't know which one I need for the pressure - the gauge goes up to 140 psi. Does anyone know from what year 911 I need a sending unit?
Thanks.

That sounds exactly like the one I have from a '70 911S.

Best,
Barry

You can also look for a date stamp on the back of the instrument. My oil temp/press combo gauge has a triangle with the number 31 inside the triangle below the apex, then below the 31 but still within the triangle are the numbers 10.70 meaning Oct, 1970.

I have seen this same dating system on the tach from my '73 914 (7.73) and on my '86 930 Turbo tach (10.86).

BTW: 31 in the first example is not the day of the month as my turbo tach has 787 in this location.

Good luck,
Barry

Thanks for the help!