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have you checked your needles and seats to make sure they'll hold 3-4 psi and not leak down. you should have a 35 pilot. I wouldn't drop the pilot jet size until you check your n/s.
 

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Discussion Starter #42
No haven't checked that, not sure how to do that, I will have to research it. I plan to pull the carbs again anyway before next winter, to clean again, so I will check that then. It started on one pull today, so that's a good sign. Not sure if I want to spend the money on a new starter, hopefully I can rebuild it or have someone do it.
 

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Discussion Starter #43
I watched a youtube video on how to rebuild a starter, doesn't look terribly difficult and a kit is around 20 bucks. The one in the video has 2 long skinny bolts that you remove to take off end caps, mine doesn't have them, it has 3 large phillips head screws, I assume you remove them and the caps with come off?
 

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Discussion Starter #44
Figured out how to take the stater apart, it didn't look to bad inside, the brushes were worn a bit unevenly so I filed them some. Looks like it's main issue is the drive gear, which is worn down some where it engages the flywheel, so will put it back together, should get a few more years out of it. I would have replaced the brushes, but surprisingly the wires connected to the brushes are soldered on and I didn't want to deal with that.
 

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Discussion Starter #45
Took the carbs apart today, the needle and seats look clean and good, so won't replace them yet, didn't do the air pressure test, just a visual inspection. Completely cleaned the carbs and resyched them and now it's running great, now if continues to satrt easily, I should be good to go. One of my choke plungers was not seating, so that was contributing to the flooding. Looks like my choke plungers are worn and a bit rough on the bottom, so I need to replace them.
 

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Discussion Starter #46
Anyone know where to purchase just the choke plungers? I have searched everywhere. Also it seems difficult to find which carb came stock on certain sleds. Pretty sure this Polaris has 38mm Mikuni's as does my '98 ZL500, not sure about the '78 Yamaha Enticer, maybe a Mikuni 36mm? They are all the round slide type.
 

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carbparts.com


Often they don't show it on their website, but you can contact them and get what you need.
 

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Discussion Starter #48
Cool, thanks. I turned the fuel off last night (I don't usually do that) and had no flooding at all, but had to choke it to get it to fire, that's different, so maybe I have it set right and it will start more consistently now.
 

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The standard XLTs ran 34 mm carbs the XCRs, 600 XC and I think the Specials (all on the XLT mono block) ran the 38 mm carbs with the high port. If you have been having flooding problems over night with your fuel turned on then you more than likely have either needle and seat issues or float level. If you look closely at your needles, I'll bet you find a small ring that has been worn into them over time. There is a difference in the needle and seat for the 34s versus the 38s. Send me a PM with your email address and I'll send you some pics of both size carbs and their respective needle/seat sets.
 

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Discussion Starter #50
Ok, left the fuel on last night, pulled one plug, it was dry and a nice light brown color. Put choke on full, pulled 3 times no fire. Tried the electric start, fired a bit but the starter keeps disengaging due to the worn gear. Held throttle wide open, started fairly quickly that way using the electric start. This is at 42 degrees and it just ran 12 hrs ago. Tomorrow I'm going to pull all 3 plugs to make sure on of the other seats is not leaking. This hard starting problem is a bit weird, especially since it starts immediately every time when it's warmed up.
 

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The plugs shouldn't get wet even if you have a bad needle and seat until you try to start it. I've had the whole bottom end fill up with fuel but I don't think that you could get the top end to fill because even if the piston was stopped so that the transfers were open, the space above the piston would be sealed and not allow it to completely fill up. Much like taking a drinking glass, turning it upside down and submerging it in a bucket of water, you'd have a sizeable air pocket.
 

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Discussion Starter #52
Ok, i am back with more problems. Fired the sled about the 3rd week of Dec and it was running well and starting pretty easily, so I thought I was done and ready to ride. I rode it around close by for about 3 weeks and then refilled the tank with fresh fuel I had just purchased. The day after I refueled it, the sled refused to start, won't even fire, this was about 10 days ago and still nada.

It has good spark in all 3 plugs, plugs are wet when pulled but doesn't appear to be flooded terribly. Tried pulling it over several times with the plugs out, let it dry out for a day or two and still nothing. One day I primed the cylinders with fuel (different from what I filled the tank with) and still not even an attempt to fire. Today I tried a small amount of starting fluid in each cylinder, seemed to almost fire then nothing.

I have tried holding the throttle wide open assuming it might be flooded, nope didn't do anything. I have encountered some strange problems, but this one takes the cake????? Help!

Plus, if you look back on last years posts I cleaned the carbs thoroughly, synched them properly and set the chokes. It had been running fine.
 

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Sounds to me like you have no spark. Pull the plugs and check for spark. Also, make sure you have your killswitch and key switch on. Stupid stuff like that can easily happen.
 

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Discussion Starter #54
It's has good spark and was running just fine before I refilled the tank, fired it up and parked it for the night. I poured some of the fuel into a jar and it looks and smells fine, as I said this is an extremely weird problem. Next is to pull the choke plungers and make sure one or more isn't stuck.
 

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Discussion Starter #55
Ok, finally figured out that it was badly flooded. I pulled the 3 drain plugs on the bottom of the motor below the exhaust manifold and at least 1-2 oz's of fuel came out of each cylinder. So since they are prone to fail and the carbs are stock 34mm Mikuni's, I am going to assume that I need to replace the needles and seats. I removed them and upon visual inspection they appear to be worn-grooved, it's hard to see, even under bright light and a magnifying glass. I don't know how to pressure text them, but since they are known to be problematic and the sled is 24 years old, they should be replaced anyway. I wonder if new gaskets come with the new needle-seat?
 

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Pretty sure you have to buy the gasket separate (float bowl gasket, that is), but at least you can get those fairly cheap. One other thing to look at is the fuel pump. When those go bad, oftentimes fuel will leak into the crankcase through the impulse line. You could isolate that by disconnecting the impulse line and see if fuel leaks out overnight. Wouldn't hurt to do all of the above, all are likely problem areas if they've never been done.
 

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Discussion Starter #57
Ok I will disconnect the impulse line and see if fuel is leaking by. I hate to spend 60 bucks on 3 needles and seats if it's not needed. It would be easy if they were obviously worn, they don't appear to be, but then my eyesight is not what it used to be.
 

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Discussion Starter #58
Ok I disconnected the impulse line, it did not contain any residual fuel and none is running out so far after an hour, I will continue to monitor it.

This is getting frustrating since the needle and seats are clean and don't appear to be worn at all and I don't have the tool to pressure test them.

Am I missing something, could it be something else?
 

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Discussion Starter #59
Still no fuel leaking from the impulse line, so I don't think theirs a problem with the pump. After further review, using a magnifying glass, I noticed some grooves and discoloration on the needle tip. After 2800 miles and 28 years, it won't hurt to replace them.
 

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