locating water pipe for cooling exhaust

[crowpeck]

just after a little help locating the pipe that allows water to flow through the exhaust on my 3d di 2007 mdl.i have had to replace the resonators due to over heating and melting the plastic thanks to the previous owner who was kind enough not to let me know about the damage.had to be towed back in with engine full of water.
i believe the problem occurs when there is a blockage in a pipe that allows water to flow through the exhaust to cool it.i have been flushing the engine at home and no water is coming out so i assume there is still a blockage and if so do not want to take it out just to have it happen again.
if any one could let me know where to locate the pipe and any other tips i would really appreciate it.
this is my first ski and really want to get out there and enjoy the 3d.cheers

 

[seadoosnipe]

951 cooling system...

The 951 cooling system is a bit more intricate than the others. They have a magneto and lower crankcase cooling system.

If you are not seeing any water flushing from the jet pump or exhaust during your back flush, then you do have a problem of some sort.

Do you know if you have any water at the top of the motor, where your cooling system indicator (tell tale) hose is.

What I believe your going to have to do is remove the outlet lines, one at a time and blow through them to find out what is stopped up.

Have you ever had the over heat alarm sound while the ski is running? Your main cooling water outlet from the engine drains back into the pump. You can see these lines back looking in from the inside, toward the back of the hull where your pump connects to the transom.

You have two lines, about 1/2" in diameter (actually metric). One is to supply the motor, one is the outlet from the motor. Check to make sure they are clear first. Then, you'll see two smaller lines, one drains the engine cylinders when you pull the ski out of the water and the other is the outlet of your crankcase heat exchanger. The heat exchanger would be the first thing I'd consider suspect.

Where your water inlet comes in from the pump to the top of the head, two lines break off and drop down to your tuned pipe water jacket. If your overheating your exhaust system, these two lines would also be suspect, take them off to make sure you have a flow of water through them.

You have one line that is called your "anti roll over bypass" line. This should not affect your engines cooling circuit.

When you connect to your backflush line, you can have your clamps or hoses prepared for removal. Turn your water on slightly when your hoses are ready. Do not use a full blast amount of water. When you get the water on, pull the lines going to your exhaust first. Check them for water flow.

You can only do this for a minute or so, then you'll need to shut the water off and start the motor. You only need to run the motor long enough to expel the water you have built up in the exhaust system. This goes against procedure of starting the motor, then the water and vice versa when shutting down. But, you have a cooling problem and that's your best way to check your flows. Be certain you do not run water more than a minute or so and not wide open. It should take about 3 or 4 minutes of solid water before you fill up your exhaust system to the point it overflows into your cylinders.

You also mentioned towing the craft back, and full of water. What was full of water, the engine? If so, did you tow the ski faster than idle? Did you pinch your water inlet line from the pump. You are not suppose to tow the ski over 15 mph and you are suppose to pinch your water line if you tow. On a dead engine, you have no exhaust pressure to keep water from building up inside the water injection of the tuned pipe, then, it will flow over into your engine.

When towing the ski, the cooling system will basically still be working. The pressure from your cooling system comes from the venturi of your pump. Towing, water is running through the venturi, effectively pushing water into your cooling system and engine. So, make sure you pinch your inlet hose while towing...........

 

[crowpeck]

thanks for the info it helped me alot and i managed to clear the blockage with air pressure.removed the blackpipe from the top of the exhaust fed the air pressure through there and took the feed pipe (the one with the red tape)off.it took a bit of pressure but it finally disloged.
the engine did get full of water but it happened before i started towing but that obviously made matters worse.i have been running it every day twice a day for a few minutes hoping to get some lubrication through the crank case even put some two stroke oil in the cylinders.i will be taking it out today and testing it.i just hope there has been no damage to the engine but with salt water???.
it seems that other people have had the same problem.there was another one at my local dealer that done the exact same thing but the over heating was worse than mine i guess it pays to make sure you are in deep enough water before you start your ski.
it's certainly been i big learing curve and i still have alot more to learn if i am going to keep on riding.which i hope i will.
thanks again for your help and information i really appreciated it.

 

[seadoosnipe]

Heat exchangers....

With the heat exchangers in the lower casing, magneto cooling, the 951 has a bit more to it than the simple cooling of all the other 2 stroke models.

You've done the right thing. You've got it running as quickly as possible. Although, no engine likes water, the idea behind these motors, because they are water toys, are expected to, at some point, see water ingestion. When this happens, you've got to get it all out and running as soon as possible. The longer it sits, the more likely it's not going to run again.

You could sink the watercraft and leave it there for a month, bring it up (and if not for the electricals) start this motor back up. When a motor has been sunk or ingested water, then drained but not lubricated, oxygen from the atmosphere starts that all to well known reaction, iron and aluminum oxide. Better known to us as "rust"..........

You should be fine. Keep it running. As long as you see water coming from the "tell tale", ride it like there is no tomorrow. That's the best you can do to help your motor...........great going!:cheers: