2001 t9.9 4 stroke

[Jakem]

Engine runs all day long....once it's warmed up. Problem I am having is to get it warmed up I need to cover up and let go of the breather pipe to carb. Filter is new...oil..spark plugs...primer bulb isn't soft it seems to stay full...filter full of gas

 

[99yam40]

not sure what you call a breather pipe, but it sounds like you have to manually choke the carb to restrict air flow.
this motor should be new enough to have an auto enrichment systen to help on cold starts until the motor warms up.
I would think you have a problem with that system/passage being plugged up or turned off

 

[Jakem]

Right..I need to manually choke it. I will check out autochoke unit

 

[boscoe99]

Yamaha calls it Primestart. An automatic fuel enrichment system. Adds extra gasoline when the motor is cold.

Not uncommon for a 21 year old motor to be seriously in need of a thorough cleaning.

 

[Jakem]

Yes I'd imagine it does

 

[Jakem]

I pulled it off...cleaned everything...o ring is good...however the fuel line from pump to carb is spitting speratically. I pulled it from pump side...

 

[Jakem]

And there's air bubbles in my fuel filter..hoses to and from primer ball are good and tight