I wonder what engine you have. My Yamaha is a 2.5 hp 4 stroke. I have no "Little Metal clips" anywhere on mine....
The fuel tank is plenty big enough for a 4 stroke, it basically uses no fuel! We can go all weekend on a tank of fuel and seldom use more than a couple of gallons a season. This includes 4 or 5 weeks cruising in Maine.
As to the way the engine runs I believe you are dealing with the same ethanol fuel issues that are driving people crazy everywhere. I think that the days of cleaning fuel bowls are pretty much gone. You need to disassemble the entire carb and clean every passage to get it to run properly again. The problem is that the water that is absorbed into the ethanol/fuel mixture is corrosive to the passages of all carburetors. As it sits and corrodes the passages slowly plug up until the engine will not run. Small displacement 4 stroke engines are at the greatest risk as their jets are the smallest and thus most easily clogged. Welcome to the world of environmentally friendly fuel and make no mistake, ethanol oxygenated fuels do far less damage to the environment when they are spilled!
I am a Vespa scooter dealer and we deal with this issue all day long. We suggest that everyone with a small displacement 4 stroke engine..
1) Use Marine Stabil in the fuel always.
2) Use Startron in the fuel (dissipates whatever water gets in).
3) Never leave fuel sitting for more than 2 or 3 weeks. This means in the outboard too, you need to get that fuel out of the carburetor. Dispose of it and buy fresh when you need more fuel. By the way, if you dispose of it before it goes bad you can put it in your cars fuel tank and just burn it up! No waste…
4) I use a “Mister Funnel” on my outboard. It works!
Follow the above advice and you will not have any problems with the engine starting or running well.
Bruce