"96" 2 stroke 60 HP Yamaha bogs down at WOT and wont idle

[WarEagle]

Help if you have any ideas. My outboard just started this out of nowhere. I in itially thought I was running out of gas. But switching tanks didnt help. New fuel pump and plugs. No help. Tied it to the dock yesterday to work on it under load and not underway. And while doing so, had 1300 RPM at full throttle (have been able to get before all of this 2700 RPM's at WOT) and placed my hand over the middle carb throat and the engine came to life! How would less air to the cylinder help it?
I will be ordering a carb rebuild kit Tuesday. Even unplugged the two yellow wires from the C.D.I. unit that says to do so when the engine runs erraticly and this helped a lot. It would ide more than 20 without dying. Any ideas? Gotta be someone out there who has had their outboard do this.????
Thanks.

[casey1240]

If your motor runs faster when you decrease the air flow at the carb, I would suspect that it is geting its air from another source. Possibly the carb is not tightened down or leaking air around a gasket. This is the simple approach, however, being that you have three carbs it could be that covering up one makes the other two work harder. Rebuilding the carbs is the best solution.

One other thought is to remove the air filter and watch to make sure your throttle plates in the carb are fully open when the throttle is in it's highest position. It's possible that your linkage is not opening these plates if the cable has slipped it's fastening. Keep us posted.

[WarEagle]

Got it running

Rebuilt carbs after soaking overnight. A lot of scale from ethanol in the gas. That Yamaha never sounded or responded so good. Thanks Yamaha Parts!!!

[harvey5560]

hoe difficult was the carb tear down, clean, rebuild and link&sync?

I have a 50 HP 2 stroke but have been affriad to try this on my own.

[WarEagle]

carb teardown

On my 60 the carbs are bolted on with the mounting plate for the "silencer". So taking them off wasnt too bad as they held in place due to the "o" ring seals to the manifold. It was putting them back on that was the hardest. One carb at a time, starting with the bottom one. Soak them over night. And be sure to "rinse" the carb cleaner out all the way as it is heavier then the gas and will tend to plug passage ways when you go to start it back up. I rinsed the carbs in gas to cut out the cleaner. Worked great. Carb rebuild kits from boats.net. What they dont provide in the kits can be cleaned and re-used. Take your time and keep parts together with the carb assy. As some of the jets are different for each carb (#1 and #2 were the same. #3 was bigger jets)
Good luck. The results will be worth the effort!!!
Oh, and a service manual is worth its weight in the money you will save taking it to a mechanic who has a dozen other motors to work on and will get to your "soon".

[pappy]

service manual

Hi War Eagle, can you tell me what service manual you use . Mine is for all Yamahas and covers so many motors it is not enough info about the one ya have.

[WarEagle]

service manual for my 1996 P60TLHU

LIT-18616-01-39
290241
P/N 6H2-28197-Z5-11
Hope that helps.