yamaha 50 hp bogging out

dddinva

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Jun 29, 2013
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I've had a year long struggle with my 2005 yamaha 50 hp. Cleaned the tanks, changed the 10 micron fuel separator, new ball, replaced fuel lines & fuel pump, cleaned carbs twice, adjusted timing, replaced plugs, checked compression did link/sinc. Its starts great, idles fine but when i put a load on it bogs down and will cut off if I do not return to idle. I can put my hands on the carb throats while running and it will pick up and run great. Ball stays hard. The jets do not spray right until I "choke" with my palms. Any suggestions would be appreciated. Stumped in FL.
 

robert graham

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When you choke it with your hand you're making the mixture more rich, so I'd venture to say you're running a lean mixture caused by plugged carb jets.....
 

99yam40

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Sep 7, 2008
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Do you have the red lever on the prime start enrichment system in the normal position?
And does the system work properly and has been cleaned?

Have you tried moving the red lever to the e position (on) and then to the off position once started and warmed up
 
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hondam

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Nov 21, 2013
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Did you use a carburator synchronizer? You definately need one to properly set those carbs. I use a vacuummate and they can be expensive and most DIYers don't have them that's why I ask.

That set of carbs is probably one of the most difficult sets to get right that I've ever done, so I wouldn't feel to bad if you need to take it in to the shop to get it right.

Did you remove the caps on the pilot screws or are they still in place?
 
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99yam40

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Maybe it would help if you posted the complete model #
We have no idea if this is a 2 or 4 stroke motor we are guessing about
 

dddinva

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This is a 50 TLR, 2-stroke. 6H5K L 1013344. I have tried moving the red emergency enrichment valve to normal and choke but seems to do better in the off position. I drilled out the brass plugs on the pilot screws, set them at 1 1/2 turns out, tried adjusting slightly but it didn't respond much. When I palm the carbs it kicks in and will run well but after returning to an idle it will bog out unless I palm the carbs again. Hondam, I am at the point of taking it to the shop and I guess your reply confirms that? Thanks for all the input so far.
 

99yam40

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the 2 stroke motor does not need the carburetor synchronizer like the 4 does.
But it still sounds like you did not get all the carbs cleaned up properly if starving for fuel
 

hondam

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Nov 21, 2013
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Didn't realize it was a 2 stroke...

I don't know if you have all this information or not but thought it might help, straight out of the Yamaha Tune Up Spec book

yam50_zpslpp3vhfj.jpg
 
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