After weeks I finally got this thing looking and running great with a bunch on new accessories. But ohhhhh these carbs! Rebuilt, 1.5 needle/seat, pop off at 40, was dumping fuel out of Venturi at idle.... Got that fixed. Now it runs great and idles great... Longer it idles, more it loads up n longer the hesitation when I go to throttle. Have low speeds out 1 3/4 turns n high speed 0... Tell me baby, where do I go from here?
-
This site contains eBay affiliate links for which Sea-Doo Forum may be compensated.
1996 Speedster Stupid Carbs! Please Help Me!!!
- Thread starter Hefty14
- Start date
- Status
BoLongo
Active Member
I can't tell you the frustration I went through with my carbs on my jet skis until I rebuilt them using the Mikuni rebuild kit. I will never rebuild another Mikuni carb without using the Mikuni kit. The kits are like $50 a carb for 20 cents worth of gaskets, but there are no substitutes; if you want it to run right, you have to use the Mikuni kit. Just rebuilt the carbs in my Challenger 1800 4 carb kits cost me $220.00
BoLongo
Active Member
I don’t think the low-speed screw will do anything for your hesitation. You are moving from the idle circuit to the mid range circuit at which point the pop off valve releases fuel into the midrange and high-speed circuits.
It sounds to me like you are starving for fuel in the transition. I would check the check valve; it is the tiny oval shaped plastic piece that is held in place with a single screw and also has to be between the alignment marks. If the check valve is allowing the fuel in the mid and high-speed circuits to drain back into the idle circuit, it will have to fill back up when you hit the throttle possibly causing the hesitation.
The check valve is slowly leaking that is why the longer you idle the greater the hesitation
When you get the rebuild kit that little check valve is hard to find, so when the carbs were rebuilt that check valve might have been lost, and the old check valve reused. I hope this helps. I attached a photo with an arrow pointing to the check valve.
Last edited by a moderator:
Yep I know the exact one ur talking about... Could this check valve allow fuel to dump out the Venturi at idle if it were bad? I was thinking at idle it was getting too much, so when I went to WOT it bogged while it burnt the excess fuel... If this valve would allow fuel to dump out Venturi while idling then it is definitely my problem! Now that I think about it, in the end if I went from a long idle to WOT the motor would actually die... If I walked my way up to WOT it kept up much bette n hesitate ruin wasn't near as noticeable... That is probably because the demand for fuel wasn't as high as a quick dump to WOT and it had time to fill back up the area where check valve is while I was easing the throttle forward... Am I making sense or am I way off here? Do they sale the check valve individually?
BoLongo
Active Member
If you have fuel coming out the center venturi during idle that would have more to do with the pop off valve or needle and seat. The pop off valve is supposed to turn off the mid and high-speed circuits during idle. When you move from idle to throttle the pop off valve releases and sends fuel to the center venturi. It sounds like you have a couple of issues going on with the carbs. It could just be the tab on the pop off valve, that tab has to be level or flush if it is too high or too low that could affect how it works.
The bad news about the check valve. They only come in the Mikuni rebuild kit. The aftermarket check valves are harder and don't seem to work as well as the Mikuni.
The bad news about the check valve. They only come in the Mikuni rebuild kit. The aftermarket check valves are harder and don't seem to work as well as the Mikuni.
Last edited by a moderator:
After I reset pop off pressure to 40 that quit happening, just wondering if it was related... When u say tab, are u talking about the arm that lifts the needle or the little hanger thing that clips on needle at top. Since I went to 1.5 needle/seat that's y I dropped my pop off to 40
BoLongo
Active Member
The tab I am talking about is the side over the top of the spring.
Yes, I would rebuild the carbs again and go back to the factory specs; you should not have to change anything if your engine is stock.
I would buy the Mikuni kits again in order to get the Mikuni check valves.
Yes, I would rebuild the carbs again and go back to the factory specs; you should not have to change anything if your engine is stock.
I would buy the Mikuni kits again in order to get the Mikuni check valves.
BoLongo
Active Member
Not sure which carb you have or if that is the correct part, but that is what the check valve looks like.
I am not sure if that is an original Mikuni check valve, but for the price you can give it a try. I have chased that dog before and ended up getting bit in the ass. If it's not an original Mikuni, I wouldn't buy it.
I am not sure if that is an original Mikuni check valve, but for the price you can give it a try. I have chased that dog before and ended up getting bit in the ass. If it's not an original Mikuni, I wouldn't buy it.
BoLongo
Active Member
Awesome sounds like you are headed in the right direction.
Rebuild the carbs to whatever the manual lists unless the carbs have been swapped for different ones. The new years of 717 used different seat sizes. If you need 1.2 needle/seat get that one don't try to make other ones work if you have a fully stock machine. You just make more work for yourself. Use the OEM spring unless you lost it. In the end if all else fails buy a new carb. They are priced very good now.
- Status
Similar threads
