1991 200hp johnson looper, fuel flow restriction, I think

[JESSIELSMALL]

On this engine the over heat and fuel flow restriction signal is the same. I thought it might be an over heat, but I pulled every hose that water runs in or out off to cool the cylinder and there is water from all and she is peeing like a champ. My problem when I start her and its sitting idleing it pops like it wants to cut off. I can ride full throttle for about a mile before the buzzer goes off, it will continue to run until I down throttle at which time it cuts off. I start it back up give it a little gas and it cuts off again. so I start up ride a little above idle for about a minute, give her gas and shes off again for about a mile, then its back to the same routine again. can any one help. I know its time for a new water fuel seperator, because I have checked it twice and the gas was a rusty color, could this be the problem or something all together different. I took her out about a month ago and had no problem at all, let it sit for a month and this is what is happening, please help. can some one tell me where to start.

[bhile]

Rusty colored gas has me wondering. Borrow a portable tank filled with fresh gas and try it.