early 1980s mariner 80 dont wanna idle and bogs out at full throttle

yodacrawler89

Recruit
Joined
Jul 19, 2009
Messages
2
ok guys srry for another ? but i have a 80 horse mariner that dont wanna idle unless i play with the choke and wont run under a load unless i play with the choke . i pulled the carbs off yesterday and they were spotless inside so i cleaned and blew them out with a compressor then reinstalled them and it seemed to run worse and if not then just about the same . i pulled the plugs cleaned them and i notice one of them wasnt as dirty as the others. i had my buddy see if i was getting spark to all of them and he said i sure was nice blue spark . so i took her down to the river and fired her up she wont start unless u give her half throttle and wont stay running unless its in nutral and at half throttle the minute u put it in gear it will run for a seconed then it boggs out but if i put it in gear then hit the choke on and off it comes out almost just fine then once it reaches top speed around 30 it will run fine till u back off the throttle to slow down then it stalls out . any ideas guys i work on motorcycles and cars but never on a boat its a little diff so im not completely dumb on this but i needs some help !

thanks so much michael
 

Chris1956

Supreme Mariner
Joined
Mar 25, 2004
Messages
27,137
Re: early 1980s mariner 80 dont wanna idle and bogs out at full throttle

I think you have two related problems. First perform the "link and synch for merc inlines" that is posted as a sticky. This will get your carbs synched with the spark advance.

Next you need to adjust the idle mixture. Start with the idle mix needles open 1-1/2 turns from lightly seated. The motor should run fine on this setting in neutral. Now put it in gear and try to accelerate. If it bogs or stalls, open the top carb 1/8 turn and try again. Repeat with bottom carb, then top carb, ect, testing after each adjustment. Eventually you will find a setting that allows reasonable idle, and good smooth acceleration.
 
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