needs a touch of throttle after rebuild to idle

[ezgoin92]

Hello all, 1994 Seadoo GTX 657X twin carb, After going through the carbs, cleaning the filters (very small amount of debris in the filters) and setting them back to the factory recommended seadoo settings from the link in the carb rebuild sticky 1 1/4 low speed and 3/8 high speed the ski starts and runs (out of water so didn't run it long) but needs a touch of throttle or it will die out. Do I get it in the water to see after running it for a bit if the issue remains or do I make an adjustment to the low speed screw or throttle setting? Guessing throttle setting adjustment would be the last adjustment not 1st? As always thanks.

- For what it is also worth incase it has bearing on recommendations, both carbs tested good for pop off pressure (31/29) and pressure/ vacuum held.
- Also in making adjustments to high or low speed screws what is the general rule? I understand in to lean it out and out for richer but when trying to adjust if necessary and diagnose idle, ramp up or high speed performance challenges what makes you determine it needs to be opened more or close down more? (hope this questions makes sense)

Thanks

 

[mikidymac]

Is the idle set to 3000rpm out of the water and 1500 in the water? The idle screw is not the same as the low speed screws.

 

[ezgoin92]

Im not sure. I dont have anything to clamp onto or around the plug to determine its RPM unless there is an easier way to identify RPM. I can look for a tool. If it is low do you adjust via the idle screw?

 

[ezgoin92]

Found an optical RPM tester I can pick up on the way to the river. Still assuming to adjust via idle set screw?

 

[mikidymac]

Yes, the idle is adjusted with the idle screw only. It is the singe screw that opens both throttle butterflies.

IF the ski has to be given throttle to stay idling then the idle is set too low.

 

[wernerml]

The idle screw sets the stop point of the throttle lever in the "nearly" closed position. This is the main setting for the idle speed.

The low speed needle screw is used to tweak the fuel flow near idle to get a smooth idle. As you lean out the mixture the engine will speed up until it is too lean, then start to slow down. (too lean above idle is dangerous to the engine's health) This screw will likely end up at the place just below peak idle rpm on the rich side, not the lean side. This range is less than half a turn.

You may need to work back and forth with both screws to set a desired idle speed where the engine also runs smoothly.

 

[ezgoin92]

The idle screw sets the stop point of the throttle lever in the "nearly" closed position. This is the main setting for the idle speed.

The low speed needle screw is used to tweak the fuel flow near idle to get a smooth idle. As you lean out the mixture the engine will speed up until it is too lean, then start to slow down. (too lean above idle is dangerous to the engine's health) This screw will likely end up at the place just below peak idle rpm on the rich side, not the lean side. This range is less than half a turn.

You may need to work back and forth with both screws to set a desired idle speed where the engine also runs smoothly.

Thanks to everyone for your suggestions. Picked up an optical rpm meter and will be working to get it set today and out on the water. Appreciate all the help.