1989 Mercruiser 3.0 Carb question

mmyers684

Cadet
Joined
Jul 14, 2010
Messages
6
I bought a 1989 searay with a mercruiser 3.0l. Bought as is. It started up when we got it. The first problem is that it wouldnt rev up or get going on the water. Figured out it was old gas. As I ran through the gas, it started running on higher rpms and gained alot of speed. After the gas was almost gone, i figured i would rebuild the carbs. I bought a rebuild kit. i cleaned everything, and put in all new gaskets and jets. It starts fine, but doesnt sound real well in idle. When i take off the throttle cable and give it a little gas, it revs up, but comes down real slow. I am wondering what could be causing this. Maybe i measured the float levels wrong or something like that. I made the float level at 9/16 or 14mm. also, i adjusted the pump rod by bending it to 29 mm. now the idle speed screw doesnt touch. I am pretty sure it is something to do with the carbs. this is my first boat, so i am figuring it out as i go. i appreciate any suggestions or ideas. if you need more info, i will do my best to inform you.
thanks
 

sxmerc

Petty Officer 1st Class
Joined
Jul 13, 2010
Messages
247
Re: 1989 Mercruiser 3.0 Carb question

Sounds like maybe a vacuum leak somewhere around the carb. Maybe you bent rod too much and butterflies aren't closing enough.
 
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