seadoo speedster twin 750

[boatmonkey82]

i have a 97 speedster and one engine is oil fouling and hydrolocking real bad
i have replaced the oil pump and still the same thing. is there any type of check valves that could be bad ?

 

[robin savell lloyd]

No check valve. How long does it have to sit being stored before you see this problem? Is it still there after you have ran it for a couple of hours? If it is still doing this after a couple of hours you may need a new engine. :cheers:

 

[boatmonkey82]

a day or two , and while running it smokes a bit at first but clears up and seems fine the rest of the day , i work on outboards and i/o for a living not these ticking time bombs . from my experiance with the ob's when they start oiling like that the seal at the real of the oil pump has failed and when it sits for a while the oil leaks into the crankcase . but that nolonger seems like the case here ... now i have a pissed customer . i have never seen one do this before .

 

[derek]

there are 2 seals on the center of the crankshaft. they (supposedly) keep the rotary valve drive gear area full of oil. they weep a little-into the crankcase induction area. sounds like yours are weeping a lot. needs a crankshaft. means it needs a motor. mine smokes a lot after a week of sitting and smokes a lot more first fire-up of the spring. i am living with it. this one sounds terminal.

 

[boatmonkey82]

i am sorry they are the 701 motors , can he do away with seadoos fine oil injection system and premix it w/o putting another crank in?

 

[derek]

actually they are 720 motors. in reality 718 cc's..called 720 and officially known as the 717 series. anybody can block off the oil pump and run premix, but that isn't the problem. the rotary valve gear train has to be full of oil. it uses the 2-stroke tank and 2 hoses to circulate oil and if you block off the oil pump you still have to feed oil to the rot valve drive area in the middle of the crankshaft. and that is where it is leaking in from.