Surging at 2000 rpm, stalls out backing off throttle.

[liquidlew]

Posting question for a bud,1998 Merc 5.7 Alpha One Gen 2, 2 bbl carb. He says it surges around 2000 rpm but gets up on plane and cruises with no problem, but then stalls out coming off throttle to idle. I already mentioned the obvious, change both fuel filters and check plugs, cap, and timing. He says those are all good and thinks maybe he can just spray carb cleaner in it. I told him it most likely needs a rebuild, but he's got a river trip planned for next week and doesn't have time to have that done so he's hoping for a miracle I guess, like maybe there is a quick and easy cure? I didn't think so either. Thoughts?

 

[alldodge]

Posting question for a bud,1998 Merc 5.7 Alpha One Gen 2, 2 bbl carb. He says it surges around 2000 rpm but gets up on plane and cruises with no problem, but then stalls out coming off throttle to idle. I already mentioned the obvious, change both fuel filters and check plugs, cap, and timing. He says those are all good and thinks maybe he can just spray carb cleaner in it. I told him it most likely needs a rebuild, but he's got a river trip planned for next week and doesn't have time to have that done so he's hoping for a miracle I guess, like maybe there is a quick and easy cure? I didn't think so either. Thoughts?

Only quick thing I would suggest with carb cleaner, is pull the top off the carb off and hope the gaskets don't tear. Clean the thing out then fill it full of carb cleaner and pump it through the channels. If that doesn't work, it will cost more money