50hp Mecury motor not running correct

[Gus]

Last fall just before I put the boat away I noticed that at full throttle the motor would surge slightly almost like it is running out of gas. Plenty of gas. did it for at least two tanks and then I put it away for the winter. What do you guys think I should be looking for this spring? I believe it's been about 4 years since it had a real in-the-shop tune. New plugs every year though, and I've run premium gas and drained the carbs each fall. Oil used was Fleetfarm's house brand don't remember the exact name. I'm wondering if the carbs are getting gunked up? Would running seafoam through a tank help that? looking for cheap solutions (if any) as a kitchen remodel project is really squeezing the belt.
btw it's about a 1980 50hp merc.
Thanks

[Surface Tension]

God I love the posts. I think the Bulter did it.
By any chance do you have a inboard gas tank?
If so I'll bet the lake was a little rough last fall when you where out?
And that mixed up the water you had in the bottom of your gas tank and the engine ran rough.
Tell me I'm right. LOL

[Chris Haley]

Could it be a weak coil??

[92python]

I had an 81 50hrs Merc 4 cyl. and it liked Seafoam. I would give it a try.

I have had similiar incidents with my 75 Merc and it always was water in the tank.

I miss how that 50 hrs. trolled.

[Steve Bakken]

I would start with the cheapest solution first- sea foam. If this doesn't work, I'd look over your fuel lines and see if you can find an air leak. Otherwise, I would probably consider a carb kit. Could be the fuel diaphram.

------------------
Steve @ Bakken's Boat Shop www.bakkensboatshop.com

[Gus]

Thanks guys, I'll go ahead and try some seafoam and if that doesn't do it go from there. Any tips on using seafoam? I've never used it in anything but I imagine the directions are pretty easy on the bottle. It does not have a built in tank. And yes that 4 cyl 50 sure does troll nice