565s short on Rpms
 

Down at LOTO trying out our new ride. We have ran the boat down to low on fuel with also cold air temps. The max Rpm I can get is 5000 at 83mph. The VV7 tach needle starts to turn red if it gets to 5000 Rpm. Can this cause the motor to go into Guardian mode. There are no alarms going off. There are from what I've heard silent codes that can just reduce power? These are the same props and setup from the previous owner. They are in perfect condition.

2014 Active Thunder 33 Evolution
565s turning Labbed 32 Maximus props with XR Sport Drive 1.50

Just to clarify you are trying to determine the performance expectations of a new to you boat, and not resolve a newly developed problem on a known boat?

Have seen a GPS reading of 92.

If you ran your tanks really low I'd start with checking your fuel filters.

scan the engine while running and verify rpms in the scan and available power - If it is reporting 100 % available power then ONE IS NOT in any form of guardian mode. Its that simple of a test - if is showing less than 100 % you have a form % of guardian mode - hence continue looking in the scan for faults and or out spec parameters.


Next is check proper fuel pressure readings while running all rpms - fuel pumps hate to be ran low or out of gas.

Change the fuel filters and check for water & crap in the fuel

Props and or any damage on the blades ?

Bottom growth and or growth on the lower unit and props ??

Is the boat carrying any extra weight ???

Next the 8.7 565 runs on 89 octane and MAX rpm is 5400.

How old is the fuel and octane level ?

Is the fuel vent venting properly ? especially from a boat that sat over the winter ??

Next is the flame arrestors clean both of them ? also if you open up the engine hatch 6 or 8 inches while running the boat does it pick up rpms ???

Boat was just filled up with new premium fuel. There's no growth on anything. The props don't have a scratch on them. There is no extra weight in the boat. I will check the fuel pressure if it ever stops raining here.

Thanks,
Jeff

Boat/setup may like snotty water. Those are some big wheels managing a wall of water in the glass. Wait for the weekend in the main channel and see if you touch the 90s.

Was the 92 at sea level ? I can't get mine to go what It did in saltwater

Was the 92 with you in the boat with the same props ? Or is this what the previous owner told you ? Have to ask and get this out of the way...

5000RPM and 83mph, is roughly 18% slip. To hit 92 with those props, you'll need to turn around 5600rpm if the slip remained constant. Is it trimmed properly? Tabs dragging?