Need help! Yamaha outboard stalling at higher speeds!!

[Tessahoc]

I'm at my wits end!! Am I missing something?

details:
Engine: 1989 Yamaha V4 130 2 stroke
boat: 1989 19 ft Grady white tournament

situation: engine seems starved for gas and higher RPM - under load
doesn't happen all the time (May happen more after I fill the tank?)
when it does- it will run at low speeds
And The bulb goes flat



what I've done:
opened the gas cap when the problem happens - no help
replaced fuel filter
changed out the "O" ring
replaced fuel lines
took out ball bearing gas check valve and replaced w/ a manual check valve
fresh gas
new plugs
new bulb

Can't replicate problem in driveway....

i would appreciate any assistance!!!!!!

mike

 

[Docksidemarineservices]

Check the dip tube in the tank for a clogged screen. That means that you have to remove the anti siphon nipple and unscrew the fitting from the tank.

 

[Tessahoc]

Check the dip tube in the tank for a clogged screen. That means that you have to remove the anti siphon nipple and unscrew the fitting from the tank.

Sorry- I forgot to mention that I did check that screen (very clean ) and replaced it as well

 

[aliboy]

How are the LP pumps?

 

[Edisto]

How are the LP pumps?

Had the sme issue. Water in the fuel system that was not picked up at low speed/idle

 

[Docksidemarineservices]

If the fuel system pans out to be ok. Check the temp of the engines while running. If the engine is not getting up to temp, you will get condensate in the combustion chamber and it will put the fire out.

If the engine is getting up to temp, pull the carbs and blow the debris out backwards thru the float seat.

 

[andreiwright]

It sound like your fuel system is clogged up. check the lines from one end to the other end if the fuel is constantly flowing or there are enough fuel flowing. It happened to me and it turn out to be a clogged fuel lines.