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Discussion Starter #1
Ok. So, I've been working on my brother's sled. It is a 1996 Polaris 600 XLT SP.

At the end of last season it would not idle on its own. So here's what I've done and I'll follow up with what it is still doing. Sorry, it's going to be long.

I pulled all three carbs. All three Pilot jets were plugged so I cleaned them out.
The bowls were fairly clean, not really any sign of build up.
Checked the Main Jet, it was a 200 which matches the sticker under the hood.
Checked the needle and seat for the float, it looked fine, no junk in or around.
I then checked the Idle air screws. They were all different, set between 1 and 1.75 turns out from lightly seated. I set them all to about 1 turn out. (To match the sticker under the hood)

Put it all back together. Won't start on its own. With or without the choke. I have to feather the throttle to get it started.
Do a little adjusting of the idle screws and now it idles only without choke. (Under 30 degrees Fahrenheit, cold motor.)

My problem with this is that I KNOW it should need the choke at this temperature and engine temperature. When the engine is cold and I get it to idle, ANY blip of the choke kills it like the kill switch is activated.

So I let it run and sure enough after about 10 minutes when its warmed up, engine dies. Won't start at all.

SO, I dive back into it. Carbs back off, double check they are clean.
Decide to pull the choke plungers, they seem fairly clean, but I clean them anyway.
I then adjust the choke plungers to a little less than 1/4" play, so I know they are bottomed out.

I then decide to sync the slides they were fairly close. I bottomed them out, put a little slack in the throttle cable, then dialed them in so they all opened at the same time, and all opened ALL the way.

Put it all back together. Still doesn't start without the throttle. So I adjust the Idle adjustment finger screw until it barely idles. Still hates the choke, even in cold temperature/cold engine.
Still dies once warmed up.

What am I missing?
Am I doing something wrong?
Maybe I'm calibrating/setting things up wrong. How would you guys do it?

Sorry for the long post, hope ya'll made it through and can lend a hand. Thanks so much.
-Andrew
 

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It sounds like you have things in order. The only thing I can point out is there is a spec for throttle cut-away. This is the amount the slides are open at idle and sitting on the throttle screws, usually measured with a tiny drill bit. You set them to spec, verify full slide operation and then use a carb sync tool (https://www.amazon.com/Uni-Syn-Carburetor-Synchronizer-Synchronizing-Balancing/dp/B073RPZKBX/ref=asc_df_B073RPZKBX/?tag=hyprod-20&linkCode=df0&hvadid=312126147596&hvpos=1o5&hvnetw=g&hvrand=3387601691785382129&hvpone=&hvptwo=&hvqmt=&hvdev=c&hvdvcmdl=&hvlocint=&hvlocphy=9005498&hvtargid=pla-567383718934&psc=1) and the throttle screws to get them all drawing the same.

Do you have full specs for the carbs? The spec has to be listed somewhere. I just posted directions to the 96-98 svc manual this morning I think it was.
 

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Discussion Starter #3
Ok, good point. I’ve seen different numbers thrown around, and I’ve heard of people just bottoming them out. I suppose that could definitely be an issue that I overlooked.

I will look for that info later today and adjust that tonight after work.

Unfortunately I don’t have a manual. Does anyone know where I could get one rather than using all the different numbers from guys on the forums?
 

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Your scenario sounds like you are over fueling at idle. When it dies check to see which plug is fouled and verify good spark.
I would also check your float levels as you have gone through everything else

Sent from my SM-G903W using Tapatalk
 

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Discussion Starter #5
I have pulled plugs after running it, and they have all been wet. You think I should adjust the float?

How do I know where to set it? And how do I adjust it?

I’ll add it to the list.
 

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I have pulled plugs after running it, and they have all been wet. You think I should adjust the float?

How do I know where to set it? And how do I adjust it?

I’ll add it to the list.
I'm pretty sure on round slides you adjust the float arm to be parallel with the carb body when held upside down.

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Discussion Starter #7
Ok. That makes sense. I will definitely have to pull them off again.

So the machine is rich, I pull all the plugs after running and they’re all wet. I think I will set the machine to stock, check the float, and adjust the slides. Then I will adjust the air screw until cold motor in cold temp wants to idle with choke.
 
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