need serious help! burning up exhaust hoses like crazy, mechanic cant figure it out

[snox550rev]

hello all, i have a 02 seadoo xp, with the 951cc motor. at the end of last season my rod berring went and I sent it in to a well known pwc mechanic in our area, he rebuilt the engine and stored it for the winter. when i got it back from him i rode it for about 4 hrs before it bunt thru an exhaust hose, the one from the pipe to the brass pipe going out the back( rubber connector hose), sent it back to him and he replaced the hose thinking it was old, got it back rode it 3 hrs and same thing diffrrent hose, this time the furthest back exhaust connection hose. this time he pulled pump apart and found the intake was pinched shut, ordered a new one and installed, after 4 hrs again it burnt a hose again, sent it back to him and he fixed and did some testing now, after 5 min of running it burns thru a new hose no problem, he says he is baffled and cant figure it out, swapped jet pump and all with a working one still burtn up hose, he says he had a thermometer and it is cool coming out the pipe but it heats up quickly after it get out of the pipe, the jetski is at his shop and everytime i call he is trying to figure it out, DOES ANYONE have any ideas what this could be, it never did this before the rebuild
please feel free to email me, lakeeffect26@gmail.com
or contact me thru here with any help, thanks and happy riding for all you that have working machines

 

[Bills86e]

It could be running lean, gas helps in the cooling process, out of time or crank out of phase (index). Is this the carbed model?

 

[snox550rev]

yes this is the carbed model

 

[6KJR]

Water regulator working? Engine getting fresh supply of water through the hoses? ARE the cooling hoses installed properly? Lean?

 

[600fusion]

My 98 xp that I just got is doing the same exact thing. I have put 3 hoses on it now and it keeps blowing them out. When I install the new one I start it with the hose and let it run for 5-10 minutes and it's fine but when it hits the lake there is a hole in one of them within minutes. When the hose blows out the exhaust gets so hot it's scary, melted a bunch of foam inside the hull! I have been using 2 1/2 inch hose from a local parts store, it in steel braided and stuff but could this be a problem? The factory one or what I assume is the factory one blew out too so I'm at a loss. I have only had the sea doo about a week and it's my first one and it seems like I work on it more than I ride it, what could be blowing out these hoses and what could I do to fix it? It seems to run strong so I really don't want to get rid of it. Thanks for any help or advice, hopefully I can get the bugs worked out with some pointers from you guys.

 

[Bills86e]

With the engine on the hose or running in the water there should be water coming out of the hose if you pull it off the fitting closest to the motor (mount) this is the feed that keeps the rubber hose joiners (couplers) from melting
The manual shows the reg being feed by the outlet on the top of the pipe but if you have the grey line feeding the reg then the top fitting will go out the back.
Make sure the lines are all clean and flowing with the engine running on the hose there needs to be water going in and out of the regulator
I would have the feed on the bottom (closest to muffler) and top going to fitting by pipe mount.

Bills86e

 

[600fusion]

Thanks for the ideas, I will check those hoses, I know there is some water making it through because when the connection blows water comes leaking out but not sure how much is supposed to be flowing out. The motor where it says caution hot always seems cool enough to touch. I'm lost, does the boot blow out and then the pipe gets hot because the water leaks out? Or is it getting to hot in the first place? Any other ideas? I'm going to check those hoses tomorrow.

 

[600fusion]

So I did some looking today and from what I can see there are two lines coming off the regulator, one larger greyish yellow one that must turn into a smaller black one half way up and one small black one. I took them both off where they connect to the exhaust and was able to blow through both of them so they aren't plugged, I'm a little confused about what one goes where. From what I gather one is a supply and one is a return? When I get the time to run it on the hose and pull those lines off the exhaust one should squirt water and the other should have nothing? Thanks for any more help, these water craft are way different than a snowmobile but I'm starting to learn.

 

[Bills86e]

Inspect the resonator internals, I read a few years ago, '98's were poorly welded and came loose. You may need to replace it if thats happened to your ski.

Bills86e