97 XP bogging issue

[XP_LBNY]

Noticed my ski is having some sort of a fuel issue recently. When I first drop it in the water it will do 30-40mph then after one good speed run it seems to bog and not want to do more than 20mph.

I replaced the spark plugs, put a fuel system cleaner in and fresh gas and it is still doing it.
There is the possible and obvious choice of a carb issue as I have replaced all the fuel lines already but my question is, is there some sort of governor or child mode that could be activated. The previous owner had his child using the machine.

I bought the ski recently and have only used it twice. It was only fresh water used prior to me and the previous owner appeared to take good care of it. Although it did sit for one whole season.
Any tips or tricks for this machine ? Thanks in advance

 

[XP 787]

What is the compression? 30-40 isn't a speed run either. When the fuel lines were replaced did you rebuild/clean the carbs? There is no child mode on that ski. Also, you state that you are recently having this problem but you have only ridden it twice. Did it run fine the first time out?

 

[XP_LBNY]

What is the compression? 30-40 isn't a speed run either. When the fuel lines were replaced did you rebuild/clean the carbs? There is no child mode on that ski. Also, you state that you are recently having this problem but you have only ridden it twice. Did it run fine the first time out?

Haven't done anything with the carbs yet. Was just looking for an easier solution before doing that. And no it's been running this way this season.... Also haven't checked the compression. Will do and I'll get back to you.


Thanks for your input. Much appreciated.
-josh

 

[racerxxx]

Gotta check compression and go thru the entire fuel system, carbs and all. And drain out that gas. There is not cutting corners on the fuel system on a 2 stroke. It will lead to certain death and you new ski will become a lawn ornament for the season.

 

[XP 787]

Gotta check compression and go thru the entire fuel system, carbs and all. And drain out that gas. There is not cutting corners on the fuel system on a 2 stroke. It will lead to certain death and you new ski will become a lawn ornament for the season.

Yes drain the fuel. I have read on this forum that any fuel additive is bad for a 2stroke because it cleans the oil off cylinder walls. What color are your fuel lines?

 

[XP_LBNY]

So I checked the compression today the front cylinder read 140 the rear read 135. I Have not been able to find what the correct compression is but most websites say they must be close in reading and that's what matters.

I have black fuel lines.

Also, I ordered a mikuni dual carb rebuild kit which will be here next week and until it arrives I'll drain the gas tank at some point and hopefully by next weekend she'll be running to top potential.

 

[XP_LBNY]

I have some experience with motors and everything in my gut is saying this is a fuel issue (haven't really worked on jet skis though) but I do have some friends with jet skis and they are saying check the impeller... Not sure if they're making valid points or not. Thoughts ?

 

[XP 787]

Bogging to me sounds like a fuel issue. With a bad impeller or wear ring it would act like a car with a slipping transmission. It will rev fine but will barely go anywhere. Also check the rear carrier bearing and make sure its greased with a grease gun.

 

[mikidymac]

To rebuild the carbs you will need 2 of everything because you have 2 carbs.
(2) Genuine Mikuni Carb kits
(2) needle and seats
(2) carb base gaskets

I would replace the fuel strainer and ON/OFF valve while you are at it as they can also cause the same bogging.

When you rebuild the carbs do not use the springs that come in the kits as they are wrong. Just reuse your old ones.

 

[XP_LBNY]

To rebuild the carbs you will need 2 of everything because you have 2 carbs.
(2) Genuine Mikuni Carb kits
(2) needle and seats
(2) carb base gaskets

I would replace the fuel strainer and ON/OFF valve while you are at it as they can also cause the same bogging.

When you rebuild the carbs do not use the springs that come in the kits as they are wrong. Just reuse your old ones.

The kit stated it was for two carbs. Should be good. And good to know about the springs. Thanks.

 

[XP_LBNY]

Finally got around to rebuilding the carbs. Ski runs great now. 50-55mph. Throttle response is amazing. Thanks everyone for their input.

If anyone on Long island is looking to ride feel free to contact me!