25 HP 2 Stroke Question

I have a 2003 25 HP 2 stroke enduro outboard at my home in in Belize. The engine has been perfect up until this week. The problem is it will randomely die while under power. It clearly feels like a lack of fuel issue. After it stops it restarts easily and runs again for awhile no problem. I replaced the fuel line and fuel tank thinking they were blocked and starving the engine for fuel. I also cleaned the engine fuel filter, the problem continued. Spark plugs are good. If it is run at idle or low speed it will go forever, the problem happens when the throttle is opened up. The more throttle applied the quicker it dies. I took off the fuel pump bolted to the engine and the diaphragms look OK but are stretched and some light shows through. I brought the pump back to the states with me as mechanics on my island are not very good.

I believe the weak diaphrams are root of the problem. Any other ideas?

[boats.net]

If the fuel pump doesn't fix it then clean the carbs.

Fuel Pump Issue

If the fuel pump doesn't fix it then clean the carbs.

I took a second look at the fuel pump diaphrams and there are no obvious holes or problems. I will replace them since it is off the engine but don't think this is going to solve the problem. The engine sits for 6 months at a time when I am in the states. I always flush with fresh water and run the fuel out before storing the engine. It is stored off the boat in my enclosed boat shed so it does sit for long periods of time.

What is the process to clean the carb? Does it need to be disassembled or can I run a spray carb cleaner?

Obviously a full disassembly is best but I would like to avoid if possible. I restore Triumphs (cars) so I am comfortable with mechanics. However, carbs are sensitive and sometimes I find I do more harm than good. Is the rebuild on a Yamaha 25 pretty straight forward or is it an art form like rebuilding a Weber?

Thanks for your help!

[boats.net]

The carbs would need to be disassembled and cleaned, they are easy to do.

[SeaHawk]

Use fogging oil for long term storage.