Please help! confusing carb issue

[lakeFreak]

I have a 90 seadoo sp with the 580 yellow motor, i bought it over the winter. I have taken this out twice now and it has great power all the way until i give it full throttle once i do that it tries to stall on me, if it doesnt stall you have to feather the throttle just to get going again. I notice if you pull the choke out ever so slightly it will let you go to full speed with out dogging down. It idles great low speed to 3/4 throttle smooth sailing, but any more is a no go. If you have any ideas please let me know. Im sure the answer is obvious however im really new to seadoos.

 

[fastboatman29212]

First place I'd start is . . .

checking the fuel lines. I am assuming the carb has been inspected and is clean. I had similar symptoms and finally it would only idle. The older fuel lines tend to break down and the inner layer turns to a gummy substance which clogs up the carb and starves the carb for fuel. Sounds like the carb is starved for fuel to me, but hey, I'd like to hear what others say before you take my advice. Let us know what the final problem/solution is.

 

[glenwhitt]

high speed circuit

3/4 to full throttle is totally high speed circuit. Could be cloged fuel filter and the likes. When you apply some choke the air intake is reduces and lessens the draw for fuel. Thats why it will keep up with the choke on. Be careful running this like it is. I am sure it is lean with choke not applied and wot.

I would replaced old lines, filter, and rebuild carbs. Just my 2.4 cents

 

[kustomkarl]

I would replace the fuel lines if you have the old gray lines. Bring a sample with you to Like Auto Zone and get the correct size. Replace the clamps to with stainless clamps while you at it. Then you need to remove and clean the carbs, using carb cleaner and some compressed air. If your careful you won't have to replace the diaphragms when you clean the carbs. Pay special attention to the 2 small fine filters inside the carbs too. Clean all the passages inside the carbs. The Low Speed screw should be at 1 1/4 turns and the High Speed screw should be set at "0". The plastic cap will only allow the High Speed screw to be turned 1/4 turn adjustment. You might have to fine tune the Low Speed screw after you run it. Be sure both carbs are in sync. with each other.

Karl

 

[lakeFreak]

Thank you guys very much for the advice, i had read on here before about the lines so i had changed them about 3 weeks ago, i checked the fuel filter and there was a little junk in it, not bad. i sprayed some carb and choke cleaner down the carb today, took it out and well it was better, it wouldnt stall at 3/4 anymore just hesitated a little the loger i played the better it got. so thank all of you very much you were very helpfull.

 

[timmyboy76]

my 2 pennies

you really nee to take the carb/s out and go thru them..gonna melt the pistons, do to "LEAN" condition