New Sea-Doo Owner Questions

[Randy H]

Hi All,

I'm a new member to the forum and a new boat and Sea-doo owner. Whenever I googled for info on Sea-doos it brought me to this site, so I figured this was the place to get all the info you need. I've been shopping for boats for a couple years and decided that you couldn't beet a Sea-Doo. No props, great manueverability, fast, and nice looking.

I just have a couple of generic questions.

First, I've been reading a lot of the threads and they talk about RAVE valves. Could someone explain these to me.

Second, how does the the cooling system work in a Sea-Doo Challenger? Does water pass thru the exhaust. The reason I ask this is because I think I may have gotten water pushed in the exhaust on a rought day on the lake and it may be causing my starting problems. The 2 stroke engines are cooled entirely by lake/sea water are they not? I guess I need to understand how the cooling system functions in a Rotax engine or the mechanics behind a Rotax vs a standard engine.

Third (and last for now), how does not starting your engines before flushing them out get water into the cylinders and require the plugs be removed to blow the water out? With most engines the cooling system would not allow water to enter the case unless a seal or gasket is leaking. Do the manuals explain a lot of these questions. The one that came with the boat from Sea-Doo is pretty vague. In fact for most issues it tell you to take the boat into an authorized dealer.

Where I am (Winnipeg) Sea-doo boats are few and far between, but lots of PWC (in fact mine is the only one one I've seen on our lake this year) so knowledge about the boats is not as abundent as it is the the US.

Thanks in advance for any feedback.

Randy

Wait....A Few more questions....

Is there an RPM level on the tach that I should get concerned with?

Generic engine questions

Rotax vs Ford? engines

2 stroke vs 4 stroke

 

[seadoosnipe]

Welcome Randy!......

Wow, that was a lot to digest at one time........!

Now I see how others feel that are reading my posts.........:rofl:

First, look at the bottom of my post, you'll see a link, "a look inside the 787". This will explain alot of what your asking....

The 2 cycle Seadoo engine has what's called a "TLCS".......or total loss cooling system. That's because there is no water pump in them to physically move water. Water supplies the engine via pressure from the nozzle.

The RAVE's......is well explained in many threads, including the one on my link.

Yes, the water cuts across your head, into the tuned pipe for preheating and then into the engine, thru the water jacket and out the exhaust and pump system.....

The reason you start the motor first is because the Rotax exhaust system using cooling water for optimum performance. If you turn on the flushing water first, then you can fill the pistons with water via the exhaust system. When the engine is running, then you have no worry. That's why it's only mentioned in flushing and towing..........towing a boat over 15 mph can also build enough pressure in the nozzle to send cooling water into the exhaust system.......

Welcome to the forum. Please click on my link below, you'll love the photo's and brief (sometimes brief anyway) descriptions of the 787.

Oh, one last question to answer....>>>ROTAX any day over a ford!!!

 

[Randy H]

Thanks for the info seadoo snipe. I just returned from the lake so I'll visit the links ASAP. Had a little problem with the boat over the weekend. Getting no beeps from the DESS, althought the engines do start?? So we ventured out anyway. After about half an hour the engies cu out and would not go again. Was just about to call 911 (water was rought and we were quickly heading towards a wall of rocks) when the engines started (still no beep). High tailed it to the beach and beached the baot before it stalled again.

In the process of trying to figure out whats wrong. All the wiring looks good and I can hear a "click" from the fuse area when I put on the DESS.