Rough Idle and will not run over half throttle '05 50HP

[lasniper]

Hello All, I have read the thread that Wally has posted, and I have a few questions. I purchased a 50 Hp back in april of this year. It was manufactured June of 05. Due to Hurricane rita recovery I have not been able to use my new toy. I ran it once and stored it in a hurry for about 2 months(Carbs had gas in them). I took it out and it ran very rough and would die out. You could not get it above half throttle. My first question is: can someone explain the seaform shock treatment ?

I think it is the carbs, could they have trash in them already ?? I have not got one full hour of run time on this motor ??

Second question : Where on boats.net can the carb kit be found for this model ?? I couldn;t find it.

Any help would be a great help ! Feeling frustrated !!!

[Mr. Ed]

Go to the Yamaha online parts catalog and select outboard, then year, then model #. The carb kits are found under the 'repair kit #1' section. Looks like for your model they are #19.

[Ken]

sniper,
Yeah, sounds like the carbs are clogged.
Carbs do not like to be left just sitting - the fuel evaporates and leaves gum and varnish.
You can try a shock treatment - sometimes that cleans them up enough. If not, you will have to tear them down, clean, and install a carb kit.
Here is the procedure I use for doing a shock treatment - it will de-carbonize the motor and clean up the fuel system somewhat. This is from an earlier post:

Two strokes build up a lot of carbon internally and need to be de-carbonized by doing a "shock treatment" with a detergent like Seafoam.
I like to do the shock treatment once a year on my C115 - in late winter when I am going thru my list of "spring make-ready".
If you use a detergent like Yamaha Ring Free or SeaFoam all the time in your fuel tank, then the carbon buildup is not as bad. Still, a lot of 2-stroke owners will de-carbonize once a year - you will get various opinions on this.
I "shock-treat" my C115 by running the following mixture thru it. This will smoke up the area pretty good, and leave a lot of carbon on the drive way:
16 oz can Seafoam
3/4 gal gas
3 oz oil (2 if oil injected)
Disconnect the fuel line at the input to the bulb and attach a three foot piece of fuel line to the bulb. Mix the above in a small container -
I use an empty 5 quart oil jug. Set the container on the deck of your boat and insert the fuel line and secure to make sure the end stays on the bottom of the container. Pump up bulb and start outboard with earmuffs and water hose, of course -run a little above idle for 15 minutes and turn off. Let sit for 15 minutes. Run again for 15 minutes. Let sit 15 minutes. Repeat until all mixture is consumed. Reattach main tank hose to bulb and run regular fuel/mixture thru motor for 10 minutes - you want to get the concentrated detergent out of the fuel system.
Now, clean up the drive way before your wife sees all that nasty carbon and makes you get rid of your boat.

After you get the carbs back in shape, try to run the motor once a week, even if it is just with the earmuffs on the driveway. If you have to let the outboard set up for more than a month w/o being run, then follow the storage procedure in the owner's manual.
Good luck [img]smile.gif[/img] ,
Ken K

[lasniper]

Hi again all,

Thanks Ken for the recap on the shock treatment. I talked with the Yamaha technician and he told me that they DO NOT put a kit in the carbs these days unless the gaskets or the O-rings are damaged. He told that they would just disassemble them and soak the in a cleaning solution.
So like Wally I bought the carb dip and tore into those carbs today...I faied better than Wally as nothing stripped out on mine all the brass seats came out fine, I only soaked the carbs for 10 minutes in stead of the 20 that was recommended by the dip maker. These just had that gummy build up left from the oil.
Very simple process indeed. Everything went back together like a dream. I did purchase new gas and a new tank just in the event that there was some trash in the old tank.
It took a little cranking till the carbs filled up.....but then that engine coughed, jumped to life and idled perfect....then reved on command like new !!
Thanks for the pointers and I hope I can contribute more in the future, and yes !! This time I followed the long term storing instructions !! But next weekend she will be in the water !!!!!

[Ken]

'sniper,
Glad you got the carbs cleaned up - which carb cleaner did you use?
And, hopefully, all of that !@#$% oil from the spill will be cleaned up by next weekend so you can get back on the water.
Good luck [img]smile.gif[/img] ,
Ken K

[lasniper]

Ken,

I used MAC'S dip....I picked it up at NAPA. The stuff was really thick, very simular to latex paint.
I work about a mile from the ship channel right behind Citgo !! Man does it stink !!!!!!!!!!!!!!!!!