7 replies to this topic

[Dani1]

Hi, im a new seadoo challenger owner. It a 1996 single engine. Ive just had total engine rebuilt, the power is there, cant see any leaks and top speed is fine once it gets going, but when in water i accelerate from a standstill, the boat revs as normal and the back end digs into the water, plenty of power but it takes a while to get onto plane. Have read it could be an outer driveshaft seal. Any advice would be welcome as Im totaly new to this and live on a resort where its not easy finding a mechanic.
Thanks

[biffdotorg]

Hi, im a new seadoo challenger owner. It a 1996 single engine. Ive just had total engine rebuilt, the power is there, cant see any leaks and top speed is fine once it gets going, but when in water i accelerate from a standstill, the boat revs as normal and the back end digs into the water, plenty of power but it takes a while to get onto plane. Have read it could be an outer driveshaft seal. Any advice would be welcome as Im totaly new to this and live on a resort where its not easy finding a mechanic.
Thanks

If the engine is reving, does it rev up fast to almost redline, or does it feel like it has an actual load? Cavitation would cause it to rev quickly with no real thrust, but would usually allow the boat to get up on plane over time.

Cavitation could be caused by a number of things. Objects in the grate or impeller, dinged or damaged impeller or wear ring etc. This would be my guess if it revs quickly as if there is minimal load, but still gets you up on plane over time.

If it revs normally and notices the load, then I would say the boat may be overloaded. Too much weight in the boat due to people, cargo etc. This is an easy one to troubleshoot as you would take everything out except the drive and test run it, so this would not be my guess.

Give your pump a good inspection, and check for anything foreign in the grate, or around the impeller. I have seen photos of some very odd items getting lodged in the pump or grate.

Good luck!

[Dani1]

Thanks for the info. Definately sounds like "Cavitation would cause it to rev quickly with no real thrust, but would usually allow the boat to get up on plane over time". This is exactly whats happening. It does get on a plane after short time and from then its running nice. Ill check the intake etc.

Many thanks

[Dani1]

Hi,
I have checked for objects in the grate and impeller but its clear. Could an oil rich mixture (im running in new engine so have a very oil rich fuel mix) cause the acceleration problem?
Thanks

[boostintt]

im curious to get an answer to the above question ^

i bought a 1999 seadoo challenger 1800, both engines have 150 psi in all cylinders. first time i turned them on it seemed as if the throttle was fully engaged. I bought new clean carbs for both engine thinking that was the issue and after installing them the throttle seemed to be not as high as before.. i took it to the water and got it up to 12mph wide open throttle. i have gas (new gas) and oil tank is full ( i didnt mix any oil on the gas) could it be that im not getting enough oil? can i just take oil out of the reservoir and premix my gas?

[Dani1]

I dont know much on this so check it first but my boat is running fine now, problem was there was way to much oil in the mix after putting in new engine. Filled it up with correct mix and after 3 or 4 hours it went perfect. Also I bought my boat with the oil injectors disconnected and I mix the oil straight in the gas tank now, previous owner said it ws safer for engine. Working fine but check it out first as im no expert.

im curious to get an answer to the above question ^

i bought a 1999 seadoo challenger 1800, both engines have 150 psi in all cylinders. first time i turned them on it seemed as if the throttle was fully engaged. I bought new clean carbs for both engine thinking that was the issue and after installing them the throttle seemed to be not as high as before.. i took it to the water and got it up to 12mph wide open throttle. i have gas (new gas) and oil tank is full ( i didnt mix any oil on the gas) could it be that im not getting enough oil? can i just take oil out of the reservoir and premix my gas?

[boostintt]

well mine is still mixing the oil with the gas. how do i go from this to premixing my gas? do i just premix my gas and drain all the oil from the oil reservoir?

[Dani1]

I dont know how to do it, I bought my boat and it already had the injectors taken off, the guy said it was a safeguard against the injectors going wrong. Still running reat though so think its ok