Losing power after 20 minutes running perfect.

[Hettie and forrest]

I have a Seadoo GS 1998 which is very well looked after and has done approx 30 hours since a full rebuild. It has always run perfectly but suddenly after 20 minutes starts surging and will eventually die. Starts perfect again after about 20 to 30 minutes and runs perfect again for 20 minutes. Checked fuel lines, filters, carb adjustments and it is not overheating.
Anyone have any ideas to help me out.
Thanks.

 

[mwat65]

Check your charging system. Run it on the hose . Rev to 4000 rpms , check battery voltage. You should be around 13.5 to 14 volts.

 

[mikidymac]

Also make sure your gas tank check valve is working.

 

[Hettie and forrest]

Thanks for the replies, I will check that out.

 

[Lhardy]

Mine ended up being needing a carb rebuild. But it kind of sounds like the same symptoms as mine.