90hp Fuel pouring out of Carbs.

[Brad_Ct]

Re: 90hp Fuel pouring out of Carbs.

I finally got the fuel pump parts and the time to put it back on. With the proper gauge I have 4 psi of fuel pressure while cranking the engine. After attaching the fuel line back onto the carbs. I cranked it over with the key off and fuel started pouring out of them. I have had these carbs. apart three times now and can not find anything wrong with them as far as float levels and the condition of the needles and seats. I ordered new needles but seats are not available. I still have a problem with the idea that I have a issue with all three carbs. doing the same thing but I guess it's possible.

 

[pnwboat]

Re: 90hp Fuel pouring out of Carbs.

Question. When you adjust the floats, are you turning the carburetor upside down and bending the tang that pushes against the needle valve so that the float is resting parallel to the carburetor body?



Sometimes you have to adjust the float so that the free end of the float is about a 1/16" farther away from the casting than factory specs because the floats are old and not as buoyant as they were when new.

A couple of questions:

Do you have an in line fuel filter between the carbs and the fuel pump? If a small speck of debris gets caught between the needle vale and seat, the carb will leak.

Where exactly is the fuel leaking from the carbs? I believe that some of the Sport Jets have a small vent tube hose that goes to each of the fuel bowls. If the hose gets plugged, the pressure inside the fuel bowl will not be at the correct level and the float/needle valve will not work like it should.

 

[Lone Duck]

Re: 90hp Fuel pouring out of Carbs.

Considering the history of the engine , and the fact that it will start with no choke. I would check the crank seals and head and exhaust gaskets.

 

[Brad_Ct]

Re: 90hp Fuel pouring out of Carbs.

Short day at work today and I found needle valves locally so I pulled the carbs. apart again, replaced the needles and set the float levels higher as suggested. I also found that the vent fittings on the bottom two carbs. were plugged even though I cleaned them out last year. Put it all back together and no more fuel leakage, I even had to choke it to get it to fire. Thanks for the help.

 

[gm280]

Re: 90hp Fuel pouring out of Carbs.

Well finally a success story for this wonderment. Assuming things gets us all in trouble some times. That is why we need others to make suggestions and then even though it goes against what you THINK you’ve already done, do it again. Glad you’re up and running now... Have a great boating season... And thanks for telling everybody what you done to fix it...more info for the next guy that has your problem... :triumphant:

 

[pnwboat]

Re: 90hp Fuel pouring out of Carbs.

Glad to hear back from you with the good news! Happy boating.

 

[Brad_Ct]

Re: 90hp Fuel pouring out of Carbs.

Unfortunitly I am not sure what actually fixed the problem since I did multiple things at once.

 

[pnwboat]

Re: 90hp Fuel pouring out of Carbs.

I would guess that new needle valves, and unplugging the vents. If the gas was coming out of the throats of the carbs, that's because the vents were plugged.