1983 mariner carb problems?

[Masonmoore]

Hi i just got this 83' 80 hp mariner running and on the muffs i noticed it was running bad. I ran some sea foam through it and tested it on the water and no difference. It stalled most of the time when put in gear and in WOT the rpms seemed to jump from high to low but it still keep me going fine. Any suggestions? Im assuming its the carbs. Thanks, mason

 

[scamp12]

Cloged jets anytime you put a motor under load it need more fuel . the change in rpm is high speed jet gumed up. These two stokes are real sensitive. Get a 1 gallon can of the carb cleaner . let them soak for a day thats the only way to remove the gum . also pick up carb cleaning tool on ebay .

 

[jrttoday]

maybe not related to your problem, but I like to run Mercury Power Tune through my 100h every couple years. Other similar products are made by practically everybody, have only used the Merc though. You have a misspelled Mercury anyway!!! :laugh: good motors!

 

[Masonmoore]

Thanks scamp12 ill take your advice and make sure i let the jets soak real good when i clean the carbs. Also could this be why I had to bump up the idle speed so it would go in gear?

 

[scamp12]

Yea if the carb has restrictions in the jets low and high. By you raiseing the idle you start. to bring in the main jet fuel to compensate for the lean mixture . If you take the carbs apart dont mess with the idle mixture srews. If you do scibe/mark and count turns for each carb and WRITE DOWN !

 

[Masonmoore]

scamp12 got it. Im not that familiar with outboard carbs so i wont be messing with the mixture screws. I will keep posted on the results. Thanks for the help!

 

[Masonmoore]

Ok so i cleaned the carbs and put new gaskets, needle seat and needles. I tried to start it and it took around 20 minutes of on and off cranking for it to start. It wouldnt idle and had fuel coming out both carbs intake and seeping out around the float bowls. Im not sure what i did wrong

 

[Masonmoore]

Ok i figured out that I had put the needles in the wrong way. But now fuel is coming out the intake and the float bowl vent jet on the top carb. Anyone know what the problem is??

 

[Chris1956]

Sure, The floats and/or inlet needles are not set correctly. You probably want to replace the floats and inlet needles and seats. Contrary to what was suggested, remove the idle mixture screws and clean all idle passages. You may find pinholes in the carb throats, that connects to the idle restrictor tube. Clean everything.

Set the floats, carb cover upside down, bend lower lever until top lever is parallel with carb cover. Turn right side up see that distance between lever sis 1/4".

Set idle mixture screws 1-1/2 turn open, and start and warm motor. Adjust idle mixture (likely a bit richer) until motor accelerates smoothly and idles at 900 RPM in neutral.

Have you checked the timing?

 

[Masonmoore]

Chris1956 i replaced the inlet needles and seats but not the floats. Thats when i started having problems. Although when i cleaned the carbs I didnt remove the mixture screws so i will be sure do do so next time. And i havent checked the timing. But thank you for the advice! One question, do the pointed part of the needles go down into the seat or out?

 

[Chris1956]

Inlet needles should be stainless with neoprene tips. The neoprene tips fit into the brass seats. Some carbs have a brass doughnut-shaped gasket under the seat, some do not. It should be obvious which seats need the gasket, and which do not.