[reeltimebrad]

On my 2004 Tiara 3200 the problems was fixed by cleaning the emergency fuel cutoff valves.  There are 2 valves that shut the flow of gas in an emergency.  One on each engine connected to the fuel supply. They are located in the engine room aft.  They are very high and cannot be seen without being in the room in between the engines.
Mine were clogged with a shellac like substance that was impeding the flow of fuel.
I had a great mechanic who was very good at problem solving.  This was the last place he looked and was surprised at the amount of buildup within the valves.  They are similar to solenoid valves(small) 2”x2”.
They did not need replacement, only cleaning and it solved my problem.
Good luck!
Email me if you have further questions.
Hotwheels996@yahoo.com
Mike

I am having a similar issue with fluctuating RPM(s) on one engine (Crusader 8.1MPI - 2006) after running for abt 3 hours at cursing speed, 3200RPM(s). No fluctuation at lower RPM(s). The problem does not repeat after engine runs at lower RPM(s) or is shut down for a period of say one hour or more. Engine temp and oil pressure remain excellent at all times. Fuel for both engines is sourced from one tank. All fuel filters replaced each season (65-75 hrs). My suspicion is that it is electronic rather than fuel related - possibly related to heat in the engine room (?). Did you find a solution to what seems to be a similar problem ? You reply will be much appreciated. Thanks.

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The shellac is from the inside of your fuel tank. Tiara will tell you it's from using ethanol fuel. Regardless I had to add fuel strainers on the ends of my pickups in the tank itself to get all the debris from plugging up my filters. Getting it all out of the tank would be a huge undertaking. If you pull the inspection plate off the top of your tank and use a flashlight to look into the bottom of the tank you'll be amazed at all the little stringers of loose resin from the tank just waiting to get sucked up.