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I have a 1985 polaris 440 SS. Basically A barn find from the family Farm. Cleaned it up and got a few minor things fixed up on it. Right now the last issue is the Carburetor. It will not start without the Help of Starting Fluid. It will take off but when it Idles down it dies. Only to start again with the Starting Fluid. It will run until it tries to idle. I need help knowing what to adjust so I can get it to Idle. Then also adjusting so I know I have enough Oil mixing in with the gas.

Thanks

Mark
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If you haven't taken the carbs off, torn them down and completely cleaned everything, then you will need to do so before it will run at all. I also have heard that starting fluid is BAD for it so don't use that anymore. Be careful when you tear down the carbs that you make sure that you count turns when removing any screws, etc. so that you put it back together exactly the way it was. While you have it apart clean EVERYTHING up very well. If that sled has been sitting around for any length of time there is sure to be varnish in the bowls and jets. Good luck -- if that doesn't do it you'll have to get more advice from the "vets".
 

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Discussion Starter #3
The carb was probably the cleanest part of the whole sled. We made sure it was good and clean. Everything was put back like it was. The main thing is it doesn't seem to get fuel or enough of the proper mixture to spark the machine to run. Hoping for a quick reference where to start to get it to turn over on it's own, then fine tune from there.
 

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Fuel at idle is controlled by the pilot jet. A good initial setting for the air screw (which controls the air to the pilot jet) is one turn out from lightly seated. If you're not getting enough fuel at idle, turn the screw in. In means less air (more fuel). If you didn't pull the pilot jet to look at it, i would do that as well. Even on carbs that look clean, the air passages to the pilot jet and the jet itself can get clogged pretty easily by debris and/or varnish. I use a piece of monofilament fishing line to probe the air passages from the front of the carb, and a strand of telephone wire with the insulation off to "floss" the jets. They can't be too clean. Blowing out the passages with compressed air is helpful as well.
 

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Assuming the carbs are good as you say they, I would look at two things: are you getting an air leak or leaks that prevent fuel from being pulled into the engine and, is (good) fuel being pumped into the carbs?

The last question is probably easiest to figure out. Even if you have to do it manually, fill the carbs through the inlet tubes. Then the engine should run when it is started - until the bowls run low. If runs like that, then figure out why it isn't getting fuel. It could be the fuel lines, the fuel pump, the impulse line. (Check the thread about the 82 Polaris Fuel problem.)

If fuel in the carbs doesn't make it run, then you may have leaking crank seals or even the rubber carb adapters attaching the carbs to the engine. Air leaks in either place will cause a lean condition if it allows fuel in in enough quantity to even run. You don't want it to run lean in either case as it will likely burn your pistons out shortly. Visually inspect the carb adapters. If they are cracked, they may be leaking. The seals - the one on the PTO end anyway, if you can get the engine running, spraying starting fluid around that seal will make the engine perk up if it is leaking there. If it won't run much at all - as you say- you might smear some grease liberally around the shaft behind the clutch to cover the seal. Grease should seal any leaks for a short while so that it will at leak run temporarily.

Compression might also be an issue. I would check the fuel/air issues first though.

A high quality TC-W mineral oil mixed at 50:1 should be used with that machine. I would give each cylinder a squirt of mixed gas through the spark plugs rather than starting fluid. If you must use an aerosol to start the engine, you might try WD-40 instead.
 

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Discussion Starter #6
I replaced the gaskets on the fuel pump and that works good. So it get's fuel and will run once started. Today I adjusted the idle mixture screw and got the sled to start for the first time with just the choke on. It will warm up loudly then when it slows down it still shuts down without Idling. Is the Idle speed control needing to open further. Or could the choke be actually choking it too much when it's suppose to Idle.
 

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The "choke" isn't. It's actually simply a valve which opens to introduce fuel into the air stream more easily than the other jets do. So it just creates a richer mixture. If it stays "on" - not sealing properly when it is closed, it may flood the engine which prevents good idling. As long as bot valves are closing with a bit of play in the cable when closed, they probably are closing well, assuming the plungers are actually sliding well inside their "tubes." In that old a machine, it might be good to check it out to make sure they are clean and free of corrosion.

You might have a case that is leaking just a bit - or you rings could be just a bit worn or not sealing well for some reason.
 

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check the boots from the carb to air box, and the boots from carb to engine. the ones on my air box were really loose and leaking and it ran horrible. looked fine, but needed replacement. i put new ones on and it wouldnt even run. had to toatlly re adjust the carbs. now with the new boots, it runs totally different, and alot better. spray some starting fluid around the boots and see if the idle surges. do this around some of the seals and see if it surges also. i had an exhaust leak too and it made it run poorly also. welded the exhaust and had to adjust it a little more to be near perfect. starts second pull all the time now. idles real good. alot more power, and much better throttle response now. the air in and out make a big difference on a 2 stroke. good luck
 
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