Audio Alarm

[Nick5910]

Have a '98 270 Sundancer w/7.4 EFI & Bravo 3.
Starts and runs without any alarms. When coming off plane and going at no wake speed, alarm starts intermittent beeping. Oil pressure 20 at idle. Temp stays constant 170.
Full oil reservoir for outdrive. No water in bilge. While increasing speed to go back on plane, alarm goes from internittent beeping to constant then goes off. Dealer states it's the oil reservoir sending unit. If the sending unit is unpluged, then no alarm occurs. To me, this doesn't make any sense because I don't see any correlation between this reservoir and slow or fast speeds.
Any thoughts would be helpful while I'm waiting for the new reservoir and sending unit.
Thanks

 

[Presentation]

Have a '98 270 Sundancer w/7.4 EFI & Bravo 3.
Starts and runs without any alarms. When coming off plane and going at no wake speed, alarm starts intermittent beeping. Oil pressure 20 at idle. Temp stays constant 170.
Full oil reservoir for outdrive. No water in bilge. While increasing speed to go back on plane, alarm goes from internittent beeping to constant then goes off. Dealer states it's the oil reservoir sending unit. If the sending unit is unpluged, then no alarm occurs. To me, this doesn't make any sense because I don't see any correlation between this reservoir and slow or fast speeds.
Any thoughts would be helpful while I'm waiting for the new reservoir and sending unit.
Thanks

Under load the drive gets hot; the oil expands and goes up the tube and into the overflow bottle resulting in the bottle pressurizing and raising the oil level.

Go slow and the drive cools off, the oil cools off, goes back down the tube, the bottle oil level and pressure drop.

.....Full oil reservoir for outdrive.....

How full is full? Full as is at the full when cold line if the engine is cold?

 

[Nick5910]

Thanks for your input.
Didn't think about expansion of the oil.
When the engine is cold the drive oil level is above the full line. When it's hot, don't see much difference that would cause the alarm. Again, unplug the resevoir float wire, no alarm. Must be something faulty with the float switch.
Thanks