Yamaha 40HP 4 cycle will not run past idle, 1-2 cyl only

[pdanker1]

Yep, that's right. Figured the ethanol settled and clogged/swelled the jets in this 4 cycle. Ran a quart of cleaner thru them, still will not hit on all three. New plugs. New in line gas filter. Ether will get it to run when sprayed in air intake. Assume it is not the computer. Is there a technician amoung us who has the fix to this??
email me direct so I will not mis your posting pdanker1@netzero.com

 

[DadTo2Marines]

Re: Yamaha 40HP 4 cycle will not run past idle, 1-2 cyl only

Sounds like the fuel pump.

 

[rodbolt]

Re: Yamaha 40HP 4 cycle will not run past idle, 1-2 cyl only

I do this every day. test spark, test compression or better have a leakdown test done, then remove and dissasemble and carefully clean the carbs.
you will need a techmate or equivalent manometer to correctly reset the throttle shutters.
your not describing a fuel pump problem your describing clogged jets.
as all the jets are brass its doubtful they swelled but the passages are tiny and they clog easily.