Twin 2009 F200s

[mmaequipment]

Both F200s are running fine until you get to about 2000 RPM, at the same time they start coughing, back-firing and stalling, cannot go over 2000 RPM, I replaced both Racors, the two smaller external filters on the engines and the fuel has just been replaced. Does anyone have additional suggestions that I could check.
Thanks

[boscoe99]

Check the anti-siphon valve if the tank has one. Better still, just remove it completely.

Check the fuel tank vent to ensure that it is free and clear.

Check the screen on the fuel pick up probe, if you have one. Better still, remove it if you have one.

Finally, check the interior condition of the fuel hoses.

I am presuming that you have but one fuel tank that supports both motors.

Better still, T a vacuum gauge into the fuel line. See what the vacuum value is when the sputtering and coughing begins. Should not be much over three or four inches of Mercury.

[99yam40]

Are you sure you do not have an alarm coming in that will put motors into RPM reduction mode?
If one gets the alarm the other will also limit RPMs if rigged up properly.

Check to make sure alarm buzzer and gauges function properly