1986 Mercruiser 3.7L 170HP Carb Question

moosejaw

Cadet
Joined
Jul 12, 2004
Messages
12
1986 3.7L 170hp c/w 300hrs on it. Always runs great. Ran it last night and heard a "spitting" sound out of carb. When it idles I see gas dripping/spitting out of the spout inside the carb on one side (gas drips and when it hits the butterfly it causes the motor to sputter). As well can't seem to to get it to idle below 1100rpm or it dies. Other than that is still runs good and has power. Carb looks spotless and is always fogged and winterized. It ran perfect first time out this year so its odd it did it this time (second time out). I know it may seem obvious just to do a carb kit but perhaps someone may have another idea?<br />Maybe the float is stuck causing gas to overflow?. Should I try a spray type carb cleaner and spray it in while it running?<br />Any ideas would be appreciated.<br /><br />Thanks
 

Rod Holder

Petty Officer 3rd Class
Joined
Jan 17, 2002
Messages
98
Re: 1986 Mercruiser 3.7L 170HP Carb Question

I have seen where the idle circuit (passage) becomes plugged and the vacuum actually draws fuel from the main jet spout, causing fuel to dribble out, which in turn causes a rich and erratic idle. The fix could be as easy as removing the idle mixture screws and giving a shot of compressed air and/or carb cleaner.<br /><br />Good luck............RH
 
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