Wet oily plugs

KVTBouy

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Jun 24, 2012
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19
I have this Yamaha 115hp V4 2stroke that used to run fine but recently developed problems. After running fine for a days fishing it brings us back to the ramp safely
and cuts off at idle and wont start again. Starts after several attempts only when chocked. will run at high rev but blogs down when lever downed.
Spark plugs are left fouled and oily. Thinking of shutting the auto oiling system giving it fuel/oil mixture to see what happens. Would appreciate any input.
 

99yam40

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Sep 7, 2008
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Starts after several attempts only when chocked. will run at high rev but blogs down when lever downed.

Have you checked to make sure the oil lever is still attached and in proper adjustment?

If you have to choke it( I believe that is what you tried to say) to restart then you are not getting enough fuel into the cylinders
 

KVTBouy

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Jun 24, 2012
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19
Definitely a case of lack of fuel to cylinders if you have to choke engine to keep it going. Checked oil lever -everything looks fine.
Will need to see if fuel pump is not bad. Appreciate your quick response-Robert and 99yam40. You guys are on the mark as always.
Motor seem to run fine most of the time, however when it bogs down a little tap on choke brings it back to life. Upon inspection I noticed oil is dumped on
spark plugs. So while the cylinders a starved of fuel, it is till getting plenty of oil due to auto lube system. Key suspects would be Carb and fuel pump i guess.
I will start with the easier one -check pump first. This is a great forum, I have learned a lot from here. Will post the results soon.
 

KVTBouy

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Jun 24, 2012
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19
Update- Pull out the fuel pump yesterday and squeezed the hand pump and bingo! Fuel squirts like a fountain. Replacement pump quoted at $115.90
-not bad compared to what i was told by worksop. They had diagnosed the problem as bad CDI which would have cost me $900 plus labour.
But I hope its just the pump. Will install it first run the engine and see, fingers crossed!
 

KVTBouy

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Joined
Jun 24, 2012
Messages
19
Looks like my misery is over. New fuel pump and the engine runs like dream again. At least in tank at home. Will try higher revs out at sea tomorrow.
 
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