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Mercury 80hp 3cyl. hard starting

J

jjacobi49

New member
Hi, I'm new to the site and have been battling a hard starting engine the last few weeks. It doesn't matter if the engine is warm or cold. I have to you use fast idle and choke to start. I removed all the gas and cleaned the tank, replaced the fuel filter, replaced the spark plugs, removed the carbs and cleaned them, and adjusted the slow idle screw to 1 3/4 out.(found it to idle good at that setting) I did find that 2 of the carbs are missing the bowl vent jet. I heard from a friend that people have removed them because they run to lean at mid throttle. Not sure if that is true. Once it starts it runs fine. Any help would be great. I'm afraid that the starter will go out if a keep cranking it to long to get it started. Thanks
 
what year 80hp , i got a 70 hp 1983 3 cyl 2 carb same proplem but its something i learned to deal with, it blows but theres no reason to dump tons of money in it ull run into the same problem down the road either that or create a new one, but what u can try is to rebuild fuel pump check valves and all, my trick is , prime to hard - turn over for three seconds, reprime turnover reprime and if she being nice she willl usally start, and my powerhead has one and a half hours on a hown and new rings, and rebuilt fuel pump and carbs,new trigger, elc box, everything u name it it new other than reeds crank and pistons, but anyways try that pump its cheap , anyone else yuo got any ideas let us know
 
Thanks for the tip! I think my 80hp is a 1988 or 1989. Serial # OB274693. I was thinking of rebuilding the fuel pump. Didn't know the fuel pump was weak if that would make it start hard.
 
i rebuilt mine and it didnt help at all, my dad had a 70 hp 1990 oil injected and u had to lift the fast idle up and down as well for it to fire but he didnt crank as long i had to but some days r better than others for me she got a mind of her own she also left me stranded 2 miles out allready, i live in fond du lac where there made, i lovem but man, so i really dont know what to think i know they shouldnt start that hard love to figure it out i got a two stroke mower sled those babys i can start in one pull you know what i mean, i could take a dump in my cat carb a it would run of that
 
Does this still have oil injection, check the oil injection lever adjustment from the carbs to the oil pump. There has a been a few revisions on those fuel pumps with new check valves etc for the oil system in the line as it mixes basically in the pump. If you are gonna do the pump buy a whole new pump kit with all the valves etc in it, they will have a manual with the kit for your motor.
 
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