Yamaha wont start 25 HP Outboard

[SteuryLover]

I just bought a Yamaha 87 25 hp outboard. Compression is good, fresh fuel, cleaned carbs, pull start. 2 times when I pulled it started up revved for about a sec then died. Fuel filter looks good and is filled with fuel. The guy I got it from though the safety red lanyard could be the wrong one, can I bypass the safety key? Anything I should look for? Thanks for everyone's help on this.

 

[JB]

Re: Yamaha wont start 25 HP Outboard

Kill switch is not the problem.

You could be running out of fuel in the carb or you could be flooding it after start. Are you releasing the choke after start?

What happens if you pump the primer bulb after start? What happens if you disconnect the fuel line after priming?

 

[SteuryLover]

Re: Yamaha wont start 25 HP Outboard

Just starting pouring rain on me again out here in SoCal. I will pull the fuel line and check to see what happens once it stops. I do believe fuel is not getting to the carb. The bulb gets nice and firm, the bulb does lose a little of its firmness once I try to start it. The fuel filter is full of fuel. I did not close the choke right away after starting it. It has only actually started a hand full of times and only after it sits for a few hours. Once it dies I cannot get it to start again. I will keep you posted once I do the above recommended. Thanks for the help.

 

[SteuryLover]

Re: Yamaha wont start 25 HP Outboard

Well pulled the fuel line going to the carb today and tried to start it. No fuel was pumped out of the fuel line. I did not pump the bulb while starting it yet, but without fuel coming out of the fuel line while pulling doesn't that point to fuel pump? The fuel filter is clean and filled with fresh fuel. When I pump the bulb with the line off the carb, fuel come out very easy. When I spray fuel in the carb it starts for a sec then dies. Thanks for the help.

 

[scottcmb]

Re: Yamaha wont start 25 HP Outboard

looks like you answered the question to your own problem!!!.......you pulled the fuel line off at the carb and then cranked it and noticed no fuel coming out of the line!!!!.......start looking at the fuel pump!!! then all line connections if pump is ok.

 

[rodbolt]

Re: Yamaha wont start 25 HP Outboard

actually you answered your own qestion just not quite what scott says.
your post is incredibly hard to decipher and contains some signs of splatter.
all the fuel primer bulb does is prime the fuel lines,filter,pump and carb fuel bowl.
once these are full the bulb is deadweight.
by the fact fuel sprays out of the carb inlet line when the bulb is pumped with the line dissconected from the carb tells me all the systems up to the carb can work.
no or low pump flow especially when hand cranking is rather normal.
the needle valves are prone to sticking if the engine sits, if they stick closed then little to no fuel will be admitted to the bowl.
open the bowl drain and then try to pump fuel.
if nothing drains out then the carb is nasty inside, if something drains it still means the carb is nasty but then most likly a clogged main jet.
ALL fuel delivered is via the main jet.
but my guess would be a stuck shut needle valve.

 

[SteuryLover]

Re: Yamaha wont start 25 HP Outboard

You are dead on, it is a stuck needle valve. I confirmed this by removing the cover and pumping the bulb. Nothing is coming out, that is why she starts right up when I spray fuel in the carb. What is the best way to correct this? Is this a carb rebuild or a better cleaning? Thanks for the fallow up on this.

 

[rodbolt]

Re: Yamaha wont start 25 HP Outboard

remove the carb, replace the needle or needle seat assy and the bowl gasket and any other worn or torn gaskets and go play.