717 Top End Rebuild problems/

[joaquin12345]

So I did a rebuild on a 717 engine. This is the first time I have done this before and I thought everything had gone good until I took the ski out to the lake.

Ok first off I did a full top end rebuild. Got a rebuild kit from FullBore. Very pleased with what I got. Installed everything per the manuel. Everything was torqued to specifics. I also went ahead and rebuilt the carb with OEM Mikuni kit. This is about the 5th carb I have redone. After I finished the rebuild put new fuel lines, fresh gas. Added 25oz of seadoo oil to 10 gallons of gas and made sure the oil reservoir was also full.

So then I took it out to the lake. Put it in the water. Oh have a fresh battery. Anyways I hit the start button for a couple 1-2sec spurts. Ski ends up starting right up. Alot of white smoke at first but then I got on the ski and once i started driving off it was great. Never went over 3/4 throttle, would not keep same speed for very long. The ski was running amazing I was really impressed never died on me or anything. I didnt push it very hard. I felt little burst of speed here and there but did not over do it. Did this for about 10-15 min then went and checked everything out on the shore. Engine felt great, warm but cool enough to be able to keep my hand on the engine and exhaust. Nothing seemed out of the ordinary. So took it out again. Same procedure. Taken it easy but enjoying it at the same time. ended up riding around in 20-30min increments for prob a total of 1hr30min.

Next thing you know i was going and the ski just died. I made a sharp turn almost a 180 degree spin but not quiet and not mashing on the throttle like when you dont have to worry about the ski. Anyways was going maybe 20 and it just died like running out of gas. Cranked it and it just spun but no effort in trying to start. Paddled to the short took out the plugs dried them off, werent very wet, then put em back in and pushed start. The ski almost started off the initial push, but then nothing continued to just turn over. Pulled plugs dried them put back in then same thing almost started off initial push then just spun. Pushed start button 2 more times then it just sounded like the starter got stuck. Tried to spin the back rod and it would move about 1/4 turn then back. Took ski out of water and everything seemed fine, nothing in the pump, Took the ski home took off the top piece off the jugs, cylinders look fine, Took the started off and same issue, no problems with the starter.

Just trying to see what you guys think as far as what I need to check next. So far,

1) Top end is fine
2) Pump is fine, nothing lodged or stuck there, pump spins freely

As far as the rotary valve gear could this be an issue. Like I said the engine turns about 1/4 turn to either side but then gets stuck when the front piston is all the way down then all the way up?? We will see what happens.

I bought this ski for $300 its a 2001 GTI with the trailer. Im out the $300 plus what I spent on the top end. Im bummed yes of course but also am using this ski as a learning ski. Kinda hooked and feeling it run good after the rebuild was great. The cylinder walls all felt fine with no scuffs. IDEAS???

 

[RebuiltSeadooBaffles]

Pull carbs off to check rotary valve, that is your next step, something (bolt or washer) could have made contact with the valve and that is why it is binding.

 

[joaquin12345]

When I pull off the carbs after that its the four bolts that hold the intake correct?? as far as whats behind that Ive never been on that side of the engine. And also does the rotary valve just pull out or do i have to get a special tool. What exactly am i looking for

 

[Britrick]

If you take the plugs out can you turn it over by hand freely ?
Did you try starting it with a little Pre mix in the plug holes ?

 

[joaquin12345]

without the plugs it still only turns about 1/4 turn. nothing really changes with our without the plugs. of course its a tiny bit easier without the plugs but still turns same amount

 

[RebuiltSeadooBaffles]

When I pull off the carbs after that its the four bolts that hold the intake correct?? as far as whats behind that Ive never been on that side of the engine. And also does the rotary valve just pull out or do i have to get a special tool. What exactly am i looking for

If you remove the carbs then yes, 4 more bolts the RV cover comes off but removing the carbs alone will allow you to check the RV itself to see whats making it hang up, if its bent then something got in there and you will likely have to change the RV drive gear as the teeth are brass and tend to shear off if the RV gets stuck while the motor spins, if its bad enough to make the crank gear walk off its centerline then it will be a bad day, lets hope that did not happen, either way pull the carbs to investigate, if you want to remove the RV cover then make sure to push on the acutal rotary valve itself when taking the cover off so it stays on the motor (to keep it in time)

 

[joaquin12345]

So tonight after work I took the carbs off and the intake. When I got to the intake half wheel thing (don't know what its called) I noticed a small maybe 1cm nick in the wheel. I did retrieve a small piece of metal/aluminum shaving from the intake. So this is what im thinking, somehow when the ski died basically it was because of the timing wheel. It somehow lodged and cut the timing off. Well then I took it to shore cleaned the plugs and while I sat there it somehow cleared out a little. When I went to retry to start it maybe gave an ummfff of 1 sec try but same thing timing went off because of the small piece gone. Anyways same thing again when I retried. well then I feel like maybe my rotary gear got tore up in the process and that's why I may be stuck. When I removed the half circle wheel the pistons moved for a about a 1/2 turn without any trouble so I feel like that's where im stuck.

Question is how do I pull out the rotary gear shaft and also lets same a tiny piece of metal got shot into the bottom end but I retrieve it which I feel is stuck around the rotary gear, what are my chances at maybe salvaging this motor. I know the odds are against me but this is a learning ski. The pistons showed some nicks at the top where I feel the pieces of whatever shot up went out the exhaust but my cyclinder walls are all untouched other then a tiny scratch to the carburetor side but I don't feel is enough to cause any problems. rings are still good Anyways throw me what you think??

 

[Britrick]

Sorry but you need to completely strip that engine down , remove any debris that may be in the crankcase and then repair any damaged caused .