motor sucked water

Hi. My nearly new 9.9 Yamaha high thrust motor got unclamped while running on reverse and gone in the water, snapped the fuel line and flooded the cylinders.
After draining the water from the carburetor, clearing the cylinders and change oil, the motor seems to run fine but no longer keeps the idle. It has to run faster then recommended when putting it into gear or it dyes. Did anyone of you got in the same trouble and found the same problem? How am I fixing it please?

 

And how much time elapsed between when it was sunk, and when the oil was changed, etc ? Salt or fresh water ?

 

modern jap 4 stroke with a problem.....
just buy a new carb
Yank 2 stokes it was unheard of for 100 years to ever replace a carb.
Now the japs have ones that if they play up you just replace them.
Borrow one from another engine to check.

 

The motor was recovered out of the water as soon as it felt into and half an hour after I did the cleaning.
Powerboat, the motor was running like a charm before the immersion, what can go wrong with the carb by having water in?

 

While there is a small chance it could be an issue with the electronics - and it won't be the modules it will be the wires / connectors. I'd second Powerabout in checking the carb out first.
You did do the drain plug on the carb, right? Do it again anyway and catch in a clean glass container - may still be some water and this is a good check Use the bulb to pass more fuel to flush and see all is clean. There is a fuel conditioner/cleaner you can add to the fuel to deal with any remaining water but lumpy idle probably means a jet is already blocked so unless you're au-fait with stripping and rebuilding carbs, by which point you change all the jets as you don't want to take apart again. the jets will cost you 100 plus and the gaskets on top.

New carbs run about 300 and many a mechanic won't waste 200 bucks of time stripping and rebuilding - a good home mechanic can save cash if he's upto the task and see's his hourly rate as Zero.

Salt or Fresh?

 

He hasn't said if it was salt water, but I think if it was, the motor should have been dismantled. If it won't idle slowly,maybe there is internal rust in the bores and rings.

 

doubt thats the problem
take a head of an engine that has been sitting for a month in hot humid environment, the bore is rusty especially if its a 4 stroke

 

Salt water and right on the crossing of a shallow bar, where sand is mixed together in the waves, that's where the motor got undone. dirt in the jets is highly possible however, water had to go through the fuel filter before reaching the carb. Water was obviously sucked in through the air intake too, would that clog up the jets?
Yes I did drain the carb from the screw at he bottom of the cup.
I got a price for a new carb at the nearest Yamaha dealer: $500. and for "pressure cleaning" the existing one:$150. (I wonder what that means?)
As soon as it was possible, lesser than an hour from the time it went under, I put 2 stroke oil in the cylinders (the only oil I had available) and run the starter motor, hopefully no rust has started. The sump oil had only a few droplets of water. Then I had to run the motor for an hour to get back home.

 

Carb has multiple air vents some the size of a small grain of sand
Thats where water and sand can get in
Bores will be fine

(I had a dealer here that gave up on tohatsu 6.0 and replaced the carb under w/tee, ran fine when it was new for a few months then it started speeding up by itself at idle)

 

I opened the carb today and found some water still in it plus little sediments of a kind of snotty algae and some sort of talcum. After taking the jets out and cleaning it all the motor seems to run fine and smooth at idle too. May be I got it right. Many thanks to you all for the advice and support.
Cheers.

 

Sound like it's good

Getting it up to full operating temp and keeping it there with fresh oil, best thing you could have done. just do a few oil changes at increased frequency e.g 5 -10 hours and you'll be good - don't expect any longer term issues.

You might want to mix up some 'salt killer' in a spray bottle with some nice warm water and go over the engine with a soft brush then rinse with a gently running freshwater hose - give it time to dry and then liberally apply good aerosol marine anti corrosion spray (the Yamaha stuff is good but you can get a generic version for about 1/4 price at most good auto stores).

 

Shall do. Thanks again