Vacuum sensor on oil return line

The oil return line should always be seeing a slight pressure (crankcase pressure) or atmospheric pressure, never a vacuum.

Rob may be referring to the oil tank (reservoir) - oil cooler - oil pump - crankcase line,  which can be expected to be under negative pressure during engine running. Why Rob would wish to separately monitor this system is a ????  

Sean you are right, the reason I want to monitor this is that I am experimenting with remote operation and this is a data point that has been identified as a key marker. 

Rob.  

Hi Rob,

"..........identified as a key marker. " For what?

The pump will cause a slight vacuum, in the oil supply line identified BUT also high pressure on the other side of its system. Most aircraft will have some way of monitoring the high pressure side (which has a very strong relationship with oil temp) as this is one of the key indicators of engine wellbeing.).

What additional engine condition monitoring will be achieved by monitoring the low pressure/vacuum side of this system?

Slightly off topic, but Sean,

that‘s an interesting comment you made („ Most aircraft will have some way of monitoring the high pressure side (which has a very strong relationship with oil temp) as this is one of the key indicators of engine wellbeing.).

Is there a link you can provide on further details?

Regards

Peter