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SOS MAJOR Fuel leak Polaris Xpress 300 1999

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Old 01-16-2017, 05:10 PM
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Default SOS MAJOR Fuel leak Polaris Xpress 300 1999

So, I have a major problem. Out of nowhere, about 2 weeks ago, the gasoline in the tank would go through the fuel line, yada yada, get to the carb, then just drain right out of the bottom vent, even though it was not started, nor had it been run in a few days. I finally decided to take the bottom tube, remove the one way valve, shorten it by a lot, and seal the end of it using a lighter, as oh well, it has TWO other vents on the carburetor. The regret. Today, I go to start it, and as I get it outside, I notice the faint smell of gasoline, but didn't take heed, as I though it was just vapor coming from the bleed tube on the gas tank. Oh my god, was I wrong. I hit the starter, and it turns a couple times, doesn't turn over, and then just gets STUCK mid-turn. I think, huh, that is odd, the battery was just charged. So, I go to pull the recoil starter, and find PRESSURE resisting me. A lot more than normal. So, I just keep pulling, but very slowly, and it was going, decreasing pressure. Then I noticed the smell of gasoline had gotten MUCH stronger, and I heard liquid hitting the ground. I look under the front, and find gasoline dripping from the first and second connection joints of the exhaust line, the ones held together by springs. I then realized what was happening. The entire cylinder had flooded with I had no idea at that moment how much it was, gas. I then decide to take off the section that makes the 180 degree turn from the engine, to the rest of the muffler, since it is only held with springs at both ends. I get the top end free, and SEE the clouds of gas vapor pouring out of there at an alarming rate. Then, as I am moving it to get the other end free, I hear a splash. The whole section is filled with gasoline. I get it free, and am covering my face and eyes to cover from and potential splashing, and my god, about a gallon and a half of gasoline poured out of there. Good thing I push the thing out of the shop before I start it. After about 5 minutes, I come back with my phone to take a photo of the puddle, and find that is only 3/4 of the size it was. Here are the two.


Photo, taken five minutes after. Puddle is now only 3/4 of the size it was. Ignore the trash, it was already there.



Same puddle, with the exhaust joint I took off added for size comparison. Ignore the trash, it was already there. Wearing my usual shop flops.

Please dear god, help me find out WHY this happened, and how the heck to stop it. Gas tank was emptied to the top of the reserve level, but I went ahead and drained the rest of it as well as turned fuel switch off. No, the switch does not leak, I have tested it before I drained the tank. At least I finally got the brakes bled and up to pressure...
 
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Old 01-16-2017, 06:39 PM
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Worn needle and seat,float level off,trash that possibly got caught under the float needle caused gas to fill the engine.If mine no sense in just cleaning a carb and hoping it solves the problem. Install a new carb kit and be done with it.POLARIS XPRESS XPLORER & 300 NEW SHINDY K&L PRO CARBURETOR REBUILD KIT 18-0393 | eBay To keep something like this from happening again always turn the fuel valve off when you're through riding. Most people forget to do this on the older models. Plus to get rid of gas that may still be in the engine,there is a 10mm drain screw at the bottom of the engine.
 
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Old 01-16-2017, 08:21 PM
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Originally Posted by old polaris tech
Worn needle and seat,float level off,trash that possibly got caught under the float needle caused gas to fill the engine.If mine no sense in just cleaning a carb and hoping it solves the problem. Install a new carb kit and be done with it.POLARIS XPRESS XPLORER & 300 NEW SHINDY K&L PRO CARBURETOR REBUILD KIT 18-0393 | eBay To keep something like this from happening again always turn the fuel valve off when you're through riding. Most people forget to do this on the older models. Plus to get rid of gas that may still be in the engine,there is a 10mm drain screw at the bottom of the engine.
A'ight. Got the kit ordered, will post when it arrives. Est. date is the 23rd, so we will see. Never seen anything like this happen before, and hopefully never will see it happen again. Is this a first for you too? Well, at least it washed some soot out of the exhaust pipe... This after finding out the head on our Suzuki is still leaking, but at least we FINALLY pinpointed the source, and are going to put some gasket paste on it. It is leaking oil onto the exhaust line from a bolt that is there to access the adjuster screws for the rocker arms. Welp, at least that will be done, and we finally got around to getting a carb kit for this Polaris, after deciding to, then sitting on our thumbs for 8 months.
 
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Old 01-17-2017, 09:21 AM
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Ain't the first time I've seen this,won't be the last time either. I don't know how many machines were brought to the shop for repair that that we discovered later that they dumped a tank of fuel on the floor that we had to clean up. Hope carb kit solves it plus always turn the fuel valve off after use just to be safe.
 
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Old 01-17-2017, 01:01 PM
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Originally Posted by old polaris tech
Ain't the first time I've seen this,won't be the last time either. I don't know how many machines were brought to the shop for repair that that we discovered later that they dumped a tank of fuel on the floor that we had to clean up. Hope carb kit solves it plus always turn the fuel valve off after use just to be safe.
Well, only difference is this time it went into the engine and exhaust pipe, but yeah, it can't be that uncommon in that format. I had started turning the fuel switch off when not using it after I sealed the vent tube on the bottom of the carb bowl, but it was about 4 days before I did. Guess this happened in that time. Jeez.
 
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Old 01-17-2017, 01:23 PM
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Originally Posted by polarisrider1203
after I sealed the vent tube on the bottom of the carb bowl Guess this happened in that time.
Yep that can do it too.. At least the fuel would have mainly gone through the carb to the floor and not through the intake straight into the engine if you hadn't done that.The combo drain/overflow vent must stay open and have a drain tube on it extended past the bash plate after you rebuild the carb. That way if it leaks it's not on or in the engine.
 
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Old 01-17-2017, 03:59 PM
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Originally Posted by old polaris tech
Yep that can do it too.. At least the fuel would have mainly gone through the carb to the floor and not through the intake straight into the engine if you hadn't done that.The combo drain/overflow vent must stay open and have a drain tube on it extended past the bash plate after you rebuild the carb. That way if it leaks it's not on or in the engine.
Well, I used a new section of tubing for this, but the reason I had sealed it in the first place was in hope of stopping the aforementioned leak (before the major flood happened), which very clearly didn't work. Still have the patchwork t-connector with the tube on the end (the one that was open, not the one running to the one way check valve). Will put a new section of tubing on the end of this and finally omit the one way valve. Completely. I think one thing that could have helped trigger the leak as the conditions in the carb were bad enough to enable this, was vacuum inside that line. As mentioned above, I had finally gone ahead and put a sealed tube over the open nub on the tee connector, so a vacuum in that area was now possible. So fuel vapor goes, exits, and then pressure in there is low, so it sucks more fuel vapor or even potentially straight liquid gasoline out from the bottom of the carb, which was the beginning of the leak. Then, when I omitted the bottom vent tubing for a sealed tube, the conditions enabling the continuous flow of fuel were still present, and so it kept flowing. Just this time right into the engine. Sometimes, I can put ~2 and ~2 together and get ~4 (the squiggly is approximately, just in case :P)
 
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Old 01-17-2017, 04:36 PM
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When I got machines like this I threw the tee away. Had a separate line from the drain,separate lines to the carb atmospheric vents and tied these to either the choke cable or throttle cable and let the ends terminate under the rear of the tank. The tees were junk to begin with.
 
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Old 01-17-2017, 06:57 PM
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Just noticed a pretty substantial crack through the clutch cover. About 75% of the length of it on a diagonal, along the underside. Any links to get a new one?
 
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Old 01-18-2017, 05:46 AM
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Your cover has been updated to a harder cover part #5433542. They're expensive but you can check for good used ones. If you go to the larger bulbous later model covers,you would have to make adaptions for the smaller exhaust dust you have on the 300. Easier to just stay with the updated one for your model.5433542 Polaris | eBay
 



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