Carb Leaking GAs? 25hp merc

[merc25rules]

I recently rebuilt my carb. When I pump my primer bulb it will not get hard.....and gas seems to be bubbling out of the middle rod right in the middle of the throat of the carb.

Im sure this has something to do with the float and lever...any ideas why im bubbling gas out of this area when i pump the primer.....FYI the engine will start but die after about 10 second

thanks

 

[Barnacle_Bill]

Re: Carb Leaking GAs? 25hp merc

Did you set the float properly? New needle?

 

[merc25rules]

Re: Carb Leaking GAs? 25hp merc

needle looked fine and im pretty sure i set the float ok. but im a newbie.

i guess i will have to take it all off and look at this again.

can you give me some real basic tips to setting the float.

maybe i put in upside down??

 

[mark_gober]

Re: Carb Leaking GAs? 25hp merc

I don't think you can put them in upside down. Typically they are hinged on one side so that you can only install them one way. You might check to see that it isn't flooded. Mine was flooded and thus wouldn't float. If that's not the problem, check the needle valve that the float pushes on. It'll either have a rubber tip or a metal tip. If it's a metal tip, that means that it seats into a rubber o ring inside the carb. Check to make sure that it's there. Rubber tip means that it seats onto a metal seat and as long as the rubber tip on the needle valve looks good, you're probably ok. That is certainly where you need to be looking though. That's why your prime bulb never stiffens up.

Mark

P.S. There really isn't a need to "set" the float. The pin should just sit in a slot and a screw usually holds the pin in place. They aren't really adjustable. It's either there or not there.

 

[cell]

Re: Carb Leaking GAs? 25hp merc

If the float isn't at the correct hight then the carb will flood,or not get enough fuel...thats the basic operation of a float.Whether its in your outboard,or your old truck.


this how you adjust a float,but you never included your year so I don't know if it applies.Click on the link.

http://www.maxrules.com/oldmercs/carburetors/1965c/1b.pdf

and that is taken from this site...lot of info.

http://www.maxrules.com/carbindex.html

 

[crappiejig]

Re: Carb Leaking GAs? 25hp merc

Also a quick check to make sure your (float) inlet needle is doing its job do this. Get a small length of fuel hose and attach to carb fuel inlet.With carb upside down,blow into hose,you should not get any air movement past needle (its seated). Now same thing carb right side up,you should get air into (empty) carb, needle not seated.

 

[merc25rules]

Re: Carb Leaking GAs? 25hp merc

it is a 1991...thanks for all the help i will look again at it tonight

 

[dannyaustin]

Re: Carb Leaking GAs? 25hp merc

I have a 1972 Mercury 402 40 HP and that was exactly what was wrong with mine. I didnt have that drawing of how to adjust those arms though. I just had to figure it out. when you bend them like that, it uses more leverage on the needle to push it up harder. Those are great instructions!

 

[cell]

Re: Carb Leaking GAs? 25hp merc

They can be found in a manual...worth the investment Id say.

 

[merc25rules]

Re: Carb Leaking GAs? 25hp merc

I really think this has something to do with the plug and jet AT THE BOTTOM OF FLAOT BOWL AND HOW IT HOOKS UP INTO THE TOP....OOPS MY 2 YR OLD HIT THE CAPS KEY!