Pulling the choke is the easiest way to kill a runaway ski. Runaway is not uncommon on a 951.
I would first try to reduce the idle, if that doesn't work you are going to have to make it richer on the low speed to cool the combustion chamber but this might lead to hesitation.
You could also have an air leak at the carb gaskets if they moved during installation.
Here you go from the legend....
"Bill's top 12 causes of runaway 947 engines.
1. Most common reason is out of the water and the idle set just 100 to 200 rpm too high. The confusing part to a 947 newby is that all other 2 stroke Sea doo engine models are set to 3000 rpm out of the water, but a 947 idles perfectly in the water when you set the idle speed at 27-2800 out of the water.
2. Allowing the head to get too hot because it is running without water going through the motor when on the trailer.
3. And some of these next reasons could be a toss up in order, Replacing the carbs onto the engine for whatever reason and setting up the throttle cable adjustment too tight at the carb cable bracket, leaving the throttle plates slightly cracked open.
4. Clogged or partially clogged low speed jets.
5. Low speed adjusters are set too far in, not allowing enough fuel to pass at idle speed.
6. Water in the gas tank that ends up inside the carbs blocking fuel flow through the jets.
7. A poor job of keeping the carb base gaskets aligned when replacing the carbs onto the manifolds equals an air leak.
8. A pin hole or split in the plastic tubing that connects the engine case pressure fitting to the check valve in the rave valve pressure supply line, or a broken check valve in that same line. This allows air to go into the engine during up strokes, leaning out the mixture.
9. One stuck needle valve that will not open.
10. Rust inside the carbs, see #6.
11. A pin hole in the fuel pump pulse line.
12. A rod hanging out the side of the cases ( or just any crack or hole in the cases ). Do not laugh, I have had customers come in saying they needed a "tune up because the motor runs away on them " only to point to that rod hanging half way out of the motor and the lower case half nearly sawed in two.
Bill O'Neal
WCM"
I don't do more than run a 951 for a few seconds in the driveway. I haven't had the problem with the smaller engined Seadoos.
