Need Help Urgently Please

[Deso89]

Hi everyone,

i Have a problem with my FL250G 4 stroke engine.

It runs perfectly fine at low speed, like 3500RPM but as soon as i give it a bit more throttle, it almost slows down and goes faster and slows down and fast... till i reduce it to the normal running speed.

Please could someone tell me what the problem could be, and how could i fix it.

I have 15 people arriving in 2 days for diving, and really need to get it sorted.

Any Help, would be appreciated

Regards

Deso89

 

[bastropdan]

It may be a fuel filter. Check for the simple things first. Fuel and fuel filters.

 

[Deso89]

It may be a fuel filter. Check for the simple things first. Fuel and fuel filters.

Hey,

i have checked both external and internal filters, checked the fuel, and replaced it with new fuel.

still doing the same thing

 

[Docksidemarineservices]

Hey,

i have checked both external and internal filters, checked the fuel, and replaced it with new fuel.

still doing the same thing

How did you check the filter? Did you replace them?

 

[Deso89]

How did you check the filter? Did you replace them?

Hi chris

they are new filters,
I also replaced all the spark plugs.

so I still had the same problem today.

please advise

 

[Docksidemarineservices]

Here is the only simple thing "you" can look for that will cause this problem. A kink or sharp bend in the fuel line. Follow the whole line.

If no sharp bend or kink is found, then a VST filter and a injector service is in your near future. It is almost always fuel related on a Yamaha four stroke, especially if the engine does a lot of sitting.