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Dominick, Marine Mechanic
Category: Boat
Satisfied Customers: 1009
Experience:  25 Years Experience as Mechanic, 20 Yrs Boat Yard Owner/Mechanic, Factory Certified
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I have a 1983 Mercury outboard 115 HP inline 6. The manual

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I have a 1983 Mercury outboard 115 HP inline 6. The manual is not clear on setting the carb float bowl needle valves. It calls for 13/32 from the face of the cover. When I set it this way it did not look like the drawing in the manual and the engine would not go above a fast idle before it stalled out. The point of measurement isn't clear to me.

I have read many posts about this engine stalling above an idle. It would appear it is a difficult one to solve for this and similar engines.

Thank you for the questionCustomer


You should have the carburetor in the diagram below and the engine is a 4 cylinder model. If so simply adjust the float to have it parallel with the housing when up side down.....This works very well and is the procedure that i use at the shop....



Customer: replied 8 years ago.
The carb you are showing is different. I have a side bowl back drag referred to as an A type in the manual. The engine is a 6 inline with three carbs.

Remove the float bowl cap and invert it (Up side down). Now take a straight edge and place it on the top of the two towers that hold the two arms of the float needle....


The little pad of the arm that touches the float spring should be at this level. To adjust bend the inner arm...(The arm not touching the float) out past the point that it is touching the fuel needle....


I hope that I explained that to where it makes sense...Read it a few times with the bowl housing inverted in your hand and held at eye level and I believe you will get the jest of what I am doing...


If not give me a shout....


Note ; The straight edge is held across the tip top of the two "towers" and to the side of the float arm that touches the float spring...The float spring is mounted on the float and should be UP....

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Thank you for the positive feedback, and yes, the $9 dollar payment was received...


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