Stalling Coming Off Plane

[JimS123]

Mercruiser 4.3 Carbed I/O, 3 years old. Starts and runs fine except when throttling back to idle speed. Then it stalls. Hard to start again, and when it does need to run at fast idle for a minute until it smoothens out. Then runs OK until slow down again.

The dealer winterized and summarized it. After getting it out of storage it wouldn't start and found out the tank was run dry. Filled it ujp and put it in the water and ran fine for a couple of days until the problem started.

That's all the info my buddy gave me. He's replacing the water separator filter today. Where else to start?

 

[alldodge]

Mercruiser 4.3 Carbed I/O, 3 years old. Starts and runs fine except when throttling back to idle speed. Then it stalls. Hard to start again, and when it does need to run at fast idle for a minute until it smoothens out. Then runs OK until slow down again.

The dealer winterized and summarized it. After getting it out of storage it wouldn't start and found out the tank was run dry. Filled it ujp and put it in the water and ran fine for a couple of days until the problem started.

That's all the info my buddy gave me. He's replacing the water separator filter today. Where else to start?

My first question is what happened to the fuel in the tank?
Next check oil level to determine if the fuel pump diaphragm has ruptured and is putting gas in the block. Is there flooding going on or lack of gas? Does it need to be pumped to restart or kept at better then half throttle to get it started? Check fuel pump pressure and if fuel is dripping down the carb