82 merc 80 hp carb issue

hi everyone, my names mike and ive got alot of info on here before but this time im completely stumped. i recently disassembled my carbs on a 1982 mercury 80 hp. after cleaning them and re installing, i cant seem to get it to idle. i sprayed some mixed fuel in the bottom carb and she fires rite up. the top carb which im assuming is for high speed sprays fine when i give it throttle. how ever the bottom carb isnt spraying at all. i am getting fuel to the bowl. another thing is when i took apart the two big jets that go into the bowls i forgot which on went where :redface: any help would be great;ly appreciated as memorial day weekend is coming up and id like to be out on the water. thanks in advance everyone

Re: 82 merc 80 hp carb issue

Each carb supplies 2 cylinders with fuel+air. I only see the one main jet on each carb. I would think each carb would have the same size main jet, either .082 or .090. Is that what you referring to?

Re: 82 merc 80 hp carb issue

its the two brass bolts that screw directly through the plate into the bowl. if these are removed gas pours out. some how no gas is spraying out of the main jet into the carb. its def. a fuel delivery problem.

Re: 82 merc 80 hp carb issue

update: chris you are right both main jets are .90. one jet was screwed in a little further then the other. i redid the carbs again and now shes getting fuel to both carbs. however now i need to adjest both air/fuel on the carbs. shes hard to fire up but once shes going she runs strong. anyone have the specs

Re: 82 merc 80 hp carb issue

Most Merc idle mxture screws are set to -1/2 turns out from lightly seated. You adjust from there.

Re: 82 merc 80 hp carb issue

ok so i adjusted mixture screw so the motor idles and throttles smoothly. how ever it still wont turn over with out giving it a little spray before cranking it over. im completely stummped. all the fuel hoses are air tight and the bulb stays pretty hard. if i look in the carbs when the motors running i can see the fuel going through the carbs via the jets. anything else you guys recomend. once again thanks so much. you been a great help

Re: 82 merc 80 hp carb issue

Do you need to spray it when it is cold, warm or both? Make sure choke (or enrichener) is working.

Re: 82 merc 80 hp carb issue

Both. I had to spray it when its cold to start it up. Then once I turn it off and let it sit for more then 5 min. I have to spray it again. I'm going to retune the carbs when I get home from work. I was so frustrated that I completely forgot about the idle speed screw. So when I got the mixture correct and smooth the idle was high and I forgot I could lower the speed with the screw lol. Shame on me. Where is the enricher located so I can double check that as well. Thanks again

Re: 82 merc 80 hp carb issue

I don't know about the enrichener on your motor. Look around for a electric solenoid and some fuel lines near the top carb. The solenoid should click and allow fuel to drain from the top carb bowl into the bottom carb, at least that is how Merc usually does it. Solenoid may be on starboard side.