Hi I have an AF2500 and after 2 years 250 hours the oil temperature fails soon after start. It reads initially then about 60F the gauge blanks (nothing shows) with "check oil temperature" audio warning.
Soon after take off (if ignored) the gauge comes alive with a reading of about minus 140F and climbs steadily into positive readings until it gets to a reasonable reading (150 to 185F - about what I have been used to in flight).
It then seems to behave normally for the rest of the flight.
The sender is a 2 wire (twisted) potted into the top of the sender and appears undamaged and secure. Initially I thought it was a bad connection, or broken wire from vibration, but the failure occurs always during warm up and then works fine once hot for the rest of the flight
Is this a likely sender failure mode? If so:
Can I replace the sender with the type that connects at the sender by attaching the existing wires (which are fed into a loom of about 12 wire pairs that goes through the firewall to the AF2500).
Unscrewing the sender from the filter housing (IO-360 engine) and screwing a new one in will be impossible without cutting the wire at the sender or removing the wire from the loom.
What sender should I get to be compatible.