mercury 60hp running problem

[tanor]

I have a 1994 60HP sst mercury 2 stroke outbd that won't stay runnig.Carbs are as clean as new inside,pump delivers pressure & volume to all 3 carbs,I have to keep pumping choke to keep it going,I can also get it to run by covering any of the carbs.after uncovering it runs for a few moments then wants to stall.Primer ball is new,filter is new,it started 2 seasons ago by intermittently not taking more than 1/3 throttle,but would go up to that point.any ideas on where to look next. and what to set the carb screws at

 

[thefairlaneman]

Re: mercury 60hp running problem

You say the carbs are clean but then refer to how it ran 2 years ago.Question is what have you done to the carbs in the past 2 years. Also are you 100% sure enough fuel is getting to the fuel pump. No matter how well it works if it is starving to get fuel into it it cant pump the amount it needs.

 

[tanor]

Re: mercury 60hp running problem

this prob. started 2 seasons ago as an intermittent loss of power when under way.I would be going 1/2-full throttle for a while then it would start to die.I could keep it going by backing the throttle to abt.1/3
at that time i was thinking spark issue.tried to isolate cylinder while under way w/no luck.
then last season i could never get past 1/4 throttle.new plugs,fuel filter,primer ball,loosened fuel cap.no change.this winter I pulled all 3 carbs,disassembled & inspected-all seemed as clean as new.ran w/water earswhile on trailer & fast idled fine.launched & couldn't keep running w/out pumping the choke or covering a carb momentarily.I checked pump(visual) good volume & pressure out of pump & to all carb inlets.

 

[tanor]

Re: mercury 60hp running problem

I have found my problem.maybe this can help others.I had plenty of volume of gas,but decided to change the fuel line & primer ball due to age.when I drained the old fuel line I noticed milky drops of gas hit the water & it didn't smell right..it appears as the gas started to dissolve the inner linning of the hose(possible ethanol contaminates or other blend)this diluted the gas. when I connected the new line & primed it,the gas smelled great & the boat runs great.note that I didn't drain the fuel but the dissolving line changed the smell.

 

[blared]

Re: mercury 60hp running problem

So the problem was bad gas, new primer bulb and fuel hose?

 

[tanor]

Re: mercury 60hp running problem

no,THE GAS WAS FRESHthis spring(ADDED TO 1/4 TANK (THAT HAD STABILIZER ADDED BEFORE STORAGE)I replaced the primer ball as a shot in the dark & a tip from a fellow boater.this didn't fix it. I was also told by another that the lines inner walls go bad as well.I did have good flow to the carbs,but changed the line anyway. when I removed the fuel line from tank to engine i noticed the strange smell & when a couple drops of gas hit the water,they were milky.
I installed the new line(w/built in primer ball)& pumped it w/1 end open,with out changing gas,the same gas smelled like it should & the boat ran great.I assume the inner wall of the line was dissolving & diluting the fuel as it passed only.

 

[blared]

Re: mercury 60hp running problem

Himmm interesting ... thank you.

 

[jeremyjamesprentice]

Re: mercury 60hp running problem

60hp Mercury intermentant problem - Mechanic so far let me down
Hey guys I have a seperate prob havent used this thread thing before.....Help
I have a 1991 - 94 60 hp mercury with 3 carbs. This problem is intermitant. Usual top speed is 30 mph. Problem is sometimes it loses power and won't go faster than 5mph. Plugs are new. Squeeze bulb has pressure. Mate has cleaned Carbs - and later so apparently did the Mechanic. Tank is vented and clean. Problem may last ten minutes or half a day when it suddenly begins to clear it's throat and slowly pick up speed and runs fine until next episode. This problem has gone on for 12 months. I am at a teather..... New fuel line, New bulb,new kill switch , new ingnition barrel, yes petrol tanks and filter was cleaned/replaced more than once Does this sound like a carb or electrical problem - I am sure a fuel problem? Or what else??? Please I need assistance I have spent over $1000 at the Mechs and still the problem raises its ugly head.
Sorry Tanor just looking for advise desperately

 

[JB]

Re: mercury 60hp running problem

Please read our rules, JJ. Hijacking old threads is frowned on, as are duplicate posts.