Polaris idles up high?

[hstrine3]

So, just spent the last 2 weeks rebuilding a top end on a 94 Polaris sl 750. All new WSM pistons and rings, all new top end gaskets replaced, Carbs rebuilt, Mikuni triple outlet pump installled. Got it started today and it idles for about 1 second then shoots up to around 4000 rpm. Played with the high and low settings a bunch setting them and resetting them to factory settings. Can't figure it out. Ski fires right up easily then almost instantly jumps up to a high RPM. Adjusted the throttle cable almost all the way out where I can feel slack in the cable at the carbs. What can be causing this? Also can someone let me know the factory Hi and low settings for a 94 sl 750 please?

[Drkvampire2001]

well an air leak can certainly cause this, another cause could be the Idler screw. its near the front of the carb rack it will adjust idle speed good chance that got moved during rebuilding. 4,000 rpms out of the water is not out of the relm, its a tad high but idle should be set in the water under load of the water, Straped to the trailer, start it up adjust the RPM to 1,300+/- 100 and should be good to go. I dont remember what my 750 revved to out of the water

[BlueFishCrisis]

I dont remember what my 750 revved to out of the water

3k - 3.5k out of the water will get you to about 1300 in the water.....

[onedollar]

I highly, highly, highly advise you to check the alignment of the throttle plates with the throttle closed. They should all be completely closed when off the throttle. If they are out of synchronization, if one or two is slightly open, it will give the running condition you have described and will give the impression that it has a massive air leak. I just fought this exact situation on my '94 750 and it sure sounds like what you are dealing with as well. I don't have your carb settings at my fingertips right now, but I can post those when I get home tonight.

So, just spent the last 2 weeks rebuilding a top end on a 94 Polaris sl 750. All new WSM pistons and rings, all new top end gaskets replaced, Carbs rebuilt, Mikuni triple outlet pump installled. Got it started today and it idles for about 1 second then shoots up to around 4000 rpm. Played with the high and low settings a bunch setting them and resetting them to factory settings. Can't figure it out. Ski fires right up easily then almost instantly jumps up to a high RPM. Adjusted the throttle cable almost all the way out where I can feel slack in the cable at the carbs. What can be causing this? Also can someone let me know the factory Hi and low settings for a 94 sl 750 please?

[hstrine3]

Thanks guys for the helpful info. I did check the throttle cable and it has plenty of slack in it. When checking the idle on the trailer it was hooked up to a garden hose don't know if that makes the difference or not. I'll probably put it in the water after work and see if I can get the idle right from there. The carb sync you're talking about I believe I'm fairly close on that, but I'll check again. I do have a 95 SL 750 also and it doesn't rev real high like that out of water, so think I got something else going on.

[onedollar]

I thought I was fairly close as well, but fairly close did not seem to be correct. As soon as I adjusted the blades absolutely closed, the problem went away.

Thanks guys for the helpful info. I did check the throttle cable and it has plenty of slack in it. When checking the idle on the trailer it was hooked up to a garden hose don't know if that makes the difference or not. I'll probably put it in the water after work and see if I can get the idle right from there. The carb sync you're talking about I believe I'm fairly close on that, but I'll check again. I do have a 95 SL 750 also and it doesn't rev real high like that out of water, so think I got something else going on.

[hstrine3]

Got the issue fixed, onedollar was right, carbs were way out of sync. Now just need to drop in the river and get some tuning done!