XP 717 bad jet pump ????? ( low rpm, rough running, taking on water )

[paul-j-fl]

When I first bought this ski it ran fine except for some hesitation on acceleration. The next time i took it out it started to bog down around 5,000 rpm, eventually maxing out at around 3,000rpm and had to be limped into the dock.

I figured the carbs were gummed up so I bought some from a known running ski with no issues, changed the fuel lines and cleaned out all the connectors.

I took it out tonight with the new carbs and a treatment of seafoam ( 1/2 a can on a full tank ). Started off nice reaching 6,500 - 7,000 rpm, but still some hesitation and not hitting that top end power. MUCH better than before though.

However, after 1/2 hour the revs dropped to around 5,000 rpm again and it ran really rough. I kept riding it to see if the seafoam would do the job and it died to 1,000rpm and I limped into the dock. It also sounded pretty rattly and whiny and louder than usual.

Also when I popped the seat there was a lot of water in the hull. Until now it's been dry after a run. Yes the drain plug was in. The only thing I did different this time was use the trim system.

Out of the water it only revs to about 5,500rpm now and is rough as hell. When i changed the carbs it would happily shoot round close to 8,000.

I'm thinking water pump because of water in hull.
The motor has about 135psi in each cylinder.

Any ideas ?

Thanks !

 

[paul-j-fl]

Nothing ?

OK. Well a little more info perhaps ?

I just looked at the exploded view of the carbs and took them apart
( the original ones ). They look pretty damn clean.
No salt intrusion,no visible signs of gunk, etc.

It could be a carb problem but by doing the same thing with
two sets of carbs it seems unlikely to me. Again - I'm by no means
an expert - that's why I'm here !

I am looking to sell it and concentrate on my 96 xp. Yes it will run great
for the test run but I don't want to do that to somebody.

I have done a number of searches for bad jetpump symptoms but
have found no results.

Please help if you can.

Thanks.

 

[Seadoobuddy]

It's only been 2-1/2 hours so give the guys some more time to answer.
If it has the gray tempo fuel lines then replace them ASAP!!!!!

the carbon seal may be leaking...it has no water pump, just the impeller to push the water out the jet and through out the engine.

 

[ocod]

start with the baiscs and see if cooling line are cracked or come off.
Check the bailers at the bottom for obstruction or clogged line.

In term of it running off,

http://www.seadooforum.com/showthread.php?40380-Carburetor-Adjustments

fuel lines

http://www.seadooforum.com/showthread.php?43149-Why-Tempo-Fuel-Hose-SUX-!!!!!!!

change your plugs, probably fouled too

x2 on carbon ring. make sure c-clip is still there pushing SS ring against carbon ring

 

[paul-j-fl]

New fuel lines, new carbs. Same symptoms. Cant seem to find anything that gives symptoms for a bad jetpump. Only been looking for 2 hours though. I said water pump but meant jetpump. Sorry about the confusion.
The frustrating thing is that it will run fine for the first 10 mins or so, then returns to the sputtering no rpm beast. Confused.

 

[paul-j-fl]

Thanks guys. I'm reading up now.

 

[paul-j-fl]

Just saw a post here with a similar issue. The advice was to check that the fuel tank is being vented properly.
I'll check it out and report back. The only line I did not replace was the fuel vent !!!!

 

[96spxpos]

Mine did the SAME EXACT thing when i first got it, you NEED to either back it in the water still on the trailer, or CAREFULLY take it for a quick cruise with the seat off...
Mine ran AMAZING for about ten minutes, then it would bog down, i'd get back to the dock, and the hull was full of water..turns out, i rode it with the seat off, and there was a tiny pisshole in the SMALL hose on the tuner pipe...i fixed that, then found ANOTHER leak on the tuner pipe, right where the "weld plug" is, which i've noticed is pretty common on older seadoo's, as they just give out over time...
i did a quick once over, then went nuts cuz i couldnt find those leaks...it wasnt until i took a step back, said "what am i not seeing", and figured it out..so just don't overlook the obvious and think the simple things are ok...

Report back with your findings please...