Getting alarm over 3000 RPM

[danpmart]

I have a 2004 Doral Intrigue with twin 5.7L Volvo Penta's. Anything under 3000 RPM I can run for hours without a problem. If I get up to 3000 I can run for about 3-4 minutes and get an alarm and lose power. Temp and pressure seem to be normal . The alarm lasts for about 30 seconds and goes off. Any thoughts on what this might be? Thanks for any suggestions!

 

[mklearl]

Temp and pressure are the only 2 alarms and will put you into safe mode if tripped. The sensor to your gauge is different than the switch which will put it into safe mode. After the 30 seconds do you regain power?
Either the sending sensor to your gauge is bad and you have a temp or pressure problem or more than likely the temp or pressure switch are bad. Are both engines tripping the alarm and do you lose power on both?

 

[danpmart]

Not sure if it is one or both engines that lose power. If I had to guess I would say both. The first two times it happened my first instinct is to pull back power immediately. The third time after I made none of my gauges were spiking was when I lost power. The alarm seemed to be coming from the cabin. By the time I got down there the alarm had quit and power was back.. 30 seconds sounds about right.

 

[mklearl]

Both engines should have an independent switch so it's unlikely they would both go off at the same time. Try to look at the rpm''s to verify loss of power and which engine. Do you have a bilge alarm? Could be the increased power brings water back to the float and sets off the alarm. Also trips the bilge float and starts pumping. Loss of power is in your head... just a thought. Usually when something goes wrong with the engine to cause safe mode it doesn't correct itself.