Yamaha Problem

[Salty Feather]

I have a 2000 Yamana 150 HP 2 stroke. While running at different RPMs the engine drops in RPMs, the drop is only 100 to 200 rpm. This problem comes and goes. I have replaced the plugs,the water seperater filter and the inline fuel filter. The Dealer I use thinks it may be the carbs but has not had the engine at thier shop to confirm this.<br />This season I winterized the engine the same way I always do but noticed that when I fogged the carbs the engine did not hesitate at all when spraying the top or bottom carbs, but did when I srayed the center one. The engine was running at idle speed. Is this normal or is it telling me the other cylinders are not firing or something ?

 

[rodbolt]

Re: Yamaha Problem

could be carbs if its a carbed motor could be fuelpumps. its best to trouble shoot before replacing anything other than maint items and tome fuelpumps every 3 years is maint.

 

[Salty Feather]

Re: Yamaha Problem

I was thinking the pumps could be the problem also, there are 2.<br />Would you rebuild them or replace them?

 

[rodbolt]

Re: Yamaha Problem

at 75 an hour I replace them, cost to much for me to rebuild them. the cost of the parts is about half of a new pump.<br /> your choice

 

[Salty Feather]

Re: Yamaha Problem

Thanks rodbolt.<br />I'll let you know the outcome.<br />Could you tell me if the motor not hesitating when I fog it is normal.