99 SPX dies letting off throttle

Note: This site contains eBay affiliate links for which SeaDooForum.com may be compensated
Status
Not open for further replies.

Austrian Rotax

Active Member
Hey Guys,

So on my last ride of the season this summer whenever I let off the throttle the ski would die unless I feathered the throttle very carefully but still most of the time it would die regardless, some history on the carbs is I had to run two different pop-off springs to get same pop-off for both carbs, couldnt find any issue with the method i was useing to test pop-off so not sure why but the ski ran great for whole season up until the last ride, it still accelerates strong and hit a top GPS speed of 94km/hr (58.4mph) on that day, I guess having single ring pistons and a SC-XO prop without intake grate helps a bit and my 150lb self. For the occasional time I could stop it from dieing if I punched the throttle right away it would not react quick and was very slow indicating not enough fuel in carb I think. Only other work I did if I remember right is I replaced the fuel pump and associated check valves (little round plastic discs). Only conclusion I can come to is the check valves maybe are bad either because I damaged them a little on install or because they were from a WSM carb kit. Thing that gets me is it ran for approx. 10 hours no problems.

I guess my question is what else could it be? The ski will run WOT all day and carb is clean. Just want to make sure I am buying the most probable part that is bad as I dont want to buy a full carb rebuild kit. Thanks
 
This may sound like a stupid question and im not trying to be an ass but is your idle set correctly? Does it idle out of the water?
 
Actually im not sure if it is set correctly so good point. Now that I remember the ski on that day was having a little trouble starting but I noticed if i held the throttle ever so slightly open when trying to start it that it would start up a bit faster so yea thats a very real possibility. Cant believe I forgot all about that, maybe the idle screw loosened off a bit or was borderline good enough before, I dont know, I just read somewhere that after idle screw just touches the tang, 2 turns in should put me in the ballpark so ill check and see if its around there tommorow.
 
Status
Not open for further replies.
Back
Top