Year, fuel ratio, repair please

[Metal Ambassador]

20 hp Merc (1978?). Serial No 5292553. <br /><br />50:1 fuel mix? <br /><br />I tried 50:1 and motor won't stay running. "Coughs" and "wheezes" then sputters out. <br /><br />Thinned out fuel a bit to approx 35:1 and same thing. Do I need new plugs now? Is the carb shot? <br /><br />Thank you!!!

 

[DHPMARINE]

Re: Year, fuel ratio, repair please

Stay with the 50:1 and rebuild the carb.Do this right after you check the spark,compression,and fuel sample.<br />DHP

 

[Paul Moir]

Re: Year, fuel ratio, repair please

Close on the year - that's a 1979 Merc.<br />50:1 is the correct mix.<br />Coughing and wheezing (ie, sneezing) are an indication of running lean on a two stroke. In all likelyhood, the carb is clogged up and need to be disassembled, cleaned and rebuilt. Order up a manual and a rebuild kit to fix it. New spark plugs woundn't be a bad idea, or a new water pump impeller unless you know it's been replaced in the last couple years. Gear lube change would be in order as well, naturally.<br /><br />Good luck!<br /><br />EDIT: Pardon, DHPMARINE!