1987 yamaha excel idles rough on 1st start after sitting overnight with motor tilted

[wwb1969]

i have a 1987 yamaha excel 225 hp that after sitting overnight with engine tilted up and then tilting back down in the morning runs rough and misfires until i get it up on plane and then runs great the remainder of the day.If i tilt the motor up when hot after running in the water it will at times loose approx 100 rpms is this normal.I have pulled apart the carbs checked needle and seats cleaned jets they are all flawless i have not done any adjustments to the carbs all the linkages are in sync with each other.The fuel is new good fuel pressure new filters new water seperator.good compression I have been chasing this for a year now and everthing looks great any can anyone put me in the right direction as to what to look for i am at a total loss at this point thanks for any help.

 

[wwb1969]

Re: 1987 yamaha excel idles rough on 1st start after sitting overnight with motor til

if there is anyone that can help out there before the motor started doing this it would run up to 5300 rpms now trimmed out it is at 4900 -5000 max is there a wearable component on the timing advance i am grasping at straws at this point and i do not or endorse shot gunning parts at something without a proper diagnosis and any help is greatly apprieciated thanks wayne.

 

[wwb1969]

Re: 1987 yamaha excel idles rough on 1st start after sitting overnight with motor til

figured it out finally the float level on the engine oil tank was sticking causing the tank to be overfilled by about 1/2 inch when tilting the motor up the oil would run down the overfill hose and into the lower carbs.