Possible 88 Force carb issue

[ForceEightyFive]

Newbie here...Ive been scouring past threads but havent been able to achieve correct diagnosis of the problem on my outboard. When I do a cold start the motor runs strong at idle. However when I shut it down it is difficult to turn back on again and when it does the idle is extremely rough (sputtering) and will die. I rebuilt fuel pump-no change. Theres also no leaks from tank to carbs. Spark is good as is compression. Also the primer bulb will not get hard. When I crank the motor over strong with the plugs out alot of gas vapor will come out of bottom two cylinders but only a small amount on the top one. Idle setting on all three carbs are at 1 1/4. Im thinking is the carbs need to be cleaned...any ideas?

 

[pnwboat]

Re: Possible 88 Force carb issue

Primer bulb not getting firm is either a bad primer bulb, blockage in the fuel line, or air leak between the bulb and the gas tank, or a needle valve in one of the carburetors is not sealing. Needle valve may be bad, or some crud is stuck between the needle valve and the needle valve seat. Installing an inline gas filter between the fuel pump and carburetors helps keep crud out of the carburetors.

 

[Solmar]

Re: Possible 88 Force carb issue

you said bulb wont get hard.Where is the fuel going???is it spilling out of your carbs???pull bulb make sure its good by pluging on end with finger and make sure check valves work in one direction(toward motor). If you can put a piece of clear tubing in place or added to fuel line to see flow physically. I think maybe your float height is off one or more carbs. Your needle wont "seat" and allow to much fuel into bowl which will draw too much fuel into carb venturi not to mention bulb wont get hard. This extra fuel is fine at cold temps when combustion needs extra fuel but when block is hot it combust easily and the extra fuel starves the air. crack your throttle plates when she wont start after warm and see if the extra air helps the engine. If so tear the carbs apart at set'em correctly.

 

[ForceEightyFive]

Likely a carb issue....Force 88

Likely a carb issue....Force 88

Thanks for the replies. I forgot to mention that I put in a new primer bulb and blew out the fuel lines with my air compressor. Ive confirmed that there is fuel flow. I disconnected the small fuel line between 1 and 2 and there was plenty of fuel when I squeezed bulb. It looks more likely then ever that the problems in the carbs, so off theyll come.I was going to use carb soak (once I pulled any rubber parts away) but there appears to a disagreement on whether or not this is a good idea, at least with these Force carbs. Not sure yet how you adjust these floats though. How complicated is that to do?

 

[Frank Acampora]

Re: Likely a carb issue....Force 88

Re: Likely a carb issue....Force 88

Simple! Invert the carbs and bend the tang. Floats should be set LEVEL with the carb body casting, under their own weight, with the carb inverted. With carbs inverted and floats resting under their own weight, the inlet needles should seal against mouth pressure. If they don't, replace the needles and seats as a set.

I like to use WD-40 to clean carbs. It dissolves all but the heaviest crud and will not harm any sealers.

After cleaning, look at the sticky syncronizing carbs and timing.

 

[pnwboat]

Re: Likely a carb issue....Force 88

Re: Likely a carb issue....Force 88

Very easy to do once you've seen how it's done. To adjust the float, you turn the carburetor upside down and bend the metal tang that pushes the needle valve closed. Set it so that the float is parallel to the carburetor body casting. Here's a video that shows it being done on a lawn mower carburetor. Notice in the beginning of the video, the float it hanging so that one end almost touches the carburetor body. After adjusting, it's pretty much parallel to the casting. You may have to tweek the adjustment after you get it back on and see that the the carb leaks.

http://www.youtube.com/watch?v=SHKR67_o7I8&feature=fvwrel

 

[ForceEightyFive]

Re: Likely a carb issue....Force 88

Re: Likely a carb issue....Force 88

Simple! Invert the carbs and bend the tang. Floats should be set LEVEL with the carb body casting, under their own weight, with the carb inverted. With carbs inverted and floats resting under their own weight, the inlet needles should seal against mouth pressure. If they don't, replace the needles and seats as a set.

I like to use WD-40 to clean carbs. It dissolves all but the heaviest crud and will not harm any sealers.

After cleaning, look at the sticky syncronizing carbs and timing.

Will do. By the way, is it enough to spray the carb parts and passages from a can or do you soak them overnight? A gallon of wd is cheap enough. Just curious what route you take.

 

[ForceEightyFive]

Re: Likely a carb issue....Force 88

Re: Likely a carb issue....Force 88

Very easy to do once you've seen how it's done. To adjust the float, you turn the carburetor upside down and bend the metal tang that pushes the needle valve closed. Set it so that the float is parallel to the carburetor body casting. Here's a video that shows it being done on a lawn mower carburetor. Notice in the beginning of the video, the float it hanging so that one end almost touches the carburetor body. After adjusting, it's pretty much parallel to the casting. You may have to do tweek the adjustment after you get it back on and see that the the carb leaks.

http://www.youtube.com/watch?v=SHKR67_o7I8&feature=fvwrel

Thanks for the vid. Looks simple enough to do.