2000 gtx di rpm

[nhmort]

I'm confused about the rpm loss after the ski is driven for a few hours.

When I first start the ski I get about 6000rpm then after its warmed up, after shutting it down and sitting for awhile, I can only get about 5500rpm. Along with hesitation getting up to speed.

The compression is 110psi on both. Low I know. Just trying to get through the summer for the kids.

Any ideas besides low compression causing this?

 

[nhmort]

Any ideas guys?

 

[nhmort]

I don't have any maintenance light on or flashing. This ski is testing my patience. Jhjesse do you have any ideas?

 

[Coastiejoe]

Get a fuel pressure test when it is cold and when it is hot. There is a chance that the fuel pump is starting to fail. The fuel starts out cold, gets warmed up and returned to the tank warmer than when it left. As this cycle continues, the fuel pump gets hotter. SO,, do a pressure test to confirm there is no loss from cold to hot.

 

[XARiUS]

I am having a similar problem on my GTX DI -- a bit higher RPM...

So I have been working on my GTX DI with a 951 Orbital Equipped for like 2 years now, had an issue with the Stator and ended up having to change the magneto cup and stator both, thats been completed and I had it back on the water for the first time since 2014 and I thought things were great.

So as it turns out, the ski runs great from start until about 6440 RPM and then it chokes, dropping down to like 5880 and then back up, like its surging. If i let off the throttle it runs great until WTO then does the same. Its intermittent, but more intermittent running correctly then not. There are no MAINT lights or beeps.

Here are my initial thoughts.

1.) Bad gas? OK.... was sea-foamed before weatherization last year and had high-octane gas in it. I topped off the tank with some 92 and added a can of SeaFoam -- still no luck.
2.) Fuel filter? -- this is a DI and i think the fuel lines are pressurized? If i change the fuel filter by the fuel pump will i lose pressurization?
3.) RAVE Valves? Not much experience working with these as my others a 717's without the Rave system, but this is my next step to clean all the RAVE Valves needed or not.
4.) Injectors? Is is possible for me to clean the injectors with something or somehow?

Any help would be appreciated, Im learning more about these DI motors and trying to decide to either keep this one and sell my GTI (717) or vise-versa. Taking it to a Seadoo dealer for a BUDS test is out of the question, there's none near.

 

[nhmort]

Thanks for the ideas guys.

 

[jhjesse]

I don't have any maintenance light on or flashing. This ski is testing my patience. Jhjesse do you have any ideas?

Sorry just saw this. Compression is a big factor for sure.
As Coastie eluded to I would start with the fuel pressure. Ever change the fuel socks on the pump or the big filter? The last one I took apart had more water in it than fuel.
With the compression getting low, chances are good that the air compressor could be getting tired as well. I would check the air pressure.
At approximately 5000 to 5500 rpms the rave valves open. Could be that they are dirty and need cleaning or the rave solenoid is bad.

 

[nhmort]

I've replaced the fuel pump last fall before I winterized it. I tested it this spring and it was 27psi after the lanyard was installed, it held there for several minutes. Then 107psi while running on the trailer. I also replaced the fuel pump filters at the pump and I just replaced the external filter outside of the tank. I did however, use longer hose between the pump and the filter for future changes. Could the length of the hose cause problems? I have about an extra 18".

I've also replaced the fuel injectors from South Bay injectors.

The raves cycle after I shut it down. So I'm thinking there is plenty of pressure there. I haven't checked the air compressor pressure, I need to do this next. Or checked for leaks. I've also cleaned the rave valves. Are there some new hoses you guys can recommend for the air system from the solenoid to the raves if I have to replace them? Those zip ties on there in my opinion don't do much. I thought they should be otiker clamps. Maybe the prior owner used zip ties.

I've always used 91 non oxy fuel and no additives. When I've stored it over the winter, I top off the gas tank so I keep the condensation to a minimum.

I also use the XPS 2 synthetic oil.

I've replaced the rectifier twice from OSD and I got a AGM battery. I also disconnect it when not in use.

The ski has 195 hours. So I'm sure it's about time to rebuild the top end. Doowacka has 4 of these and he's only done the top end of them. I'm not all that thrilled to get into the bottom end.

I read up and down on the forum, and it seems that the rectifiers, battery, and fuel pump are the usual problems.

I've also read the Seadoo maintenance manual several times so I think I have an understanding of the ski.

Here's the other issue, it's at my lake home about 2 hours away so I can't easily work on it. Plus my kids are damn near riding it from dawn to dusk. I realize that you guys need some answers from my tests before we can continue on. But I'm frustrated and looking for other usual issues for this DI ski.

Thanks

 

[nhmort]

One more thing, I can't seem to justify buying a Candoo for $400.

After reading here, it seems like all of those sensors are never the problem or am I kidding myself?

 

[jhjesse]

Unless you are throwing a code a candoo isn't going to help. 107psi combined pressure is perfect.
With all you have done I would check for a loose or cracked hose coming off the rave solenoid, air compressor, etc. Could be that something is not leaking or causing a problem until it warms up.

 

[nhmort]

That seems to make more sense.

Thanks