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I know this has been beat to death by lots of in different groups and from different areas, but a friend of mine who is also a member and is knowledgeable about these sleds has a theory about why there seems to be so much trouble with clogged filters on these sleds... I have owned other brands of fuel injected snowmobiles and other toys and never had an issue .. I fuel up my motor vehicles at the same gas station most of the time and never heard tell of any big issue with fuel filters... his theory and it is the best explanation I have seen to date for this problem... belt dust being sucked in by the tank vent. just about every person you talk with that changes out the filters say they are black as tar... no way is this just coming from dirty gas., if it was then how come the other brands aren't having issues like this..thought I would throw this out there as there is some pretty knowledgeable guys lurking around here.. not meant to start an argument but rather to get some opinions on this theory... It makes sense to me. if this is the case a small filter on the vent should fix the problem.. one guy I know always filters his gas before it goes in the sled and filters looked like tar...
 

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Where is the tank vent located
The schematic makes it appear to terminate on the clutch side? Im assuming that the check valve the vents connected to is to allow for air in. I think the OP could be on to something. Certainly couldn't hurt to install a filter on the inlet.
 

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The schematic makes it appear to terminate on the clutch side? Im assuming that the check valve the vents connected to is to allow for air in. I think the OP could be on to something. Certainly couldn't hurt to install a filter on the inlet.
There has to be a reason other than dirty gas.. I have changed quite a few gas filters over the past 50 years and I have not seen a filter in the condition that I am seeing with those sleds. I owned argos, outboard motors and numerous vehicles.. biggest issue I have seen would be water in the fuel... whether gas or diesel....There are guys here that are having way more problems with dirty gas filters then they would have if taking it from a rusty drum.. I know a guy who uses a mr funnel religously and he had black filters.... don't see how anything can get past one of those funnels... brp needs to address this problem and get to the bottom of what is causing this to be such and issue..
 

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My Gas Vent, on my 2017 WT 900 Ace, tube runs into the horizontal tube between skis and that seems like that would be very well protected from sucking belt dust, but? Are other vernt tubes just open to the atmosphere near the Drive belts?\]

I just picked this sled up at the end of the season here in Maine and it only has 262 miles on it so I guess I will have to wait and see what happens

SWTMan#13
 

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Then there needs to be a constant low pressure in the fuel tank to draw particles in from the atmosphere. I don’t think the tanks are lower pressure than atmosphere. Do you see particles in the vent line? There would be a tell tale sign if clutch particles are entering the tank.
 

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.. his theory and it is the best explanation I have seen to date for this problem... belt dust being sucked in by the tank vent. just about every person you talk with that changes out the filters say they are black as tar... no way is this just coming from dirty gas.
I think your on to something but i believe the problem is following to close behind 2 smokers not belt dust
 

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All of my Gen 4 sleds and all that I have seen have positive pressure in the fuel tank. Take the cap off and it releases pressure. To be honest I don't understand how these tanks are vented other than the line that goes outside the sled by the a arm
 

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Yammie, what kind of junk are you seeing in the filters? I see some black crud and like the GM trucks of old (late 80s to late 90s) I think it's fuel pump rotor material. They generate a ton of it over time and it's got to go somewhere. I thought you may be on to something with the belt dust but after checking my vent hose, it's pretty clean inside.
 

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I like the theories about pump rotor dust or belt dust, either sounds plausible. I haven't seen that degree of discoloration on my sleds' fuel filters. What I have observed in my atv's and tractors is that the black rubber fuel lines degrade over time and seem to cause filter clogging like in the photo above. Ethanol fuel is really rough on the hoses. Anyone have to replace a fuel line?
 

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Folks. I like the idea of putting a piece of cloth over the end over the vent hose. Don't see where it will hurt. This is a big issue that has been going on for many years. Limping home with a plugged fuel system is no fun. Wrecks the day for sure. And an unscheduled "pulling the pump to clean the sock" is not a quick job. Looking forward to digging in and putting this one behind us, instead of under us. :- )

SUV1, I recall you mentioning some issues with the inside of an older tank wearing or flaking? Could this have been from the float rubbing on the inside of the tank? And, if it is, is there anyway to "adjust the float arm to not touch the inside lining of the tank?

Another "suspect" is the fuel level float its self, suspecting some wear material is from the ID of the float to the fuel level shaft.

I noticed wear on the float on a rebuild last summer, along with the described black coating on all the socks and filters. There were some wear spots on the outside of the float and there was wear on the I.D. of the float as well. I initially replaced the float with an aftermarket float. The aftermarket float was not a good idea. It wore very quickly and plugged the pump sock half way through the season. When I took the pump assembly out, found the aftermarket float was badly worn on the ID, not anywhere on the outside. The bigger hunks on the sock looked to be from the float. Some of the black coating on the filter might have been from the pump brushes, didn't look at it under the microscope. I cleaned the socks, replaced the filter, and spent real money on a new factory float / level sensor (since you can't buy just the float.) The rest of the season was without fuel issues.

The half baked plan is to check the sock and filters this summer and, regardless of what I find - put a very thin I.D. sleeve inside the float and see if that helps. Thoughts on this plan are more than welcome. :- )

Looking forward to see the results of the different ideas.

_Jack
 

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I have replaced several filters and cleaned socks on my 1200's with lots of miles. Socks seem to collect a gritty material that reminds me of sand. Filters collect a very fine substance that appears to be rust particles. Nothing black. I have never tried to analyze the material collected.

I have always suspected that somewhere I get a tank of gas at a snowmobile stop and the fuel dispensed is unfiltered.

I almost never hear of cars filters plugging up and they use a lot more fuel in their life. I think what we have here is a filter system with insufficient capacity for the service life of a sled today. The capacity was fine when sleds ran 5k miles for their life but now with 4 strokes it is too short. BRP is selling some filters at a very high margin so it makes them look pretty greedy too.

BRP engineering should take a look at their standard practices in designing their filtering systems as clearly their customers think there is a problem
 
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I've come across an inordinate amount of degraded filter screens aka petcock filters recently. The fact that the gunk from the gas or replacement air vent is getting past these filters or blocking them entirely is a concern.

I have seen sled fuel tanks degrade from gas and heat over time tiny dust like black particles clogging. It's rare but it happens. Also the replacement air vent hoses do on occasion degrade and release junk into the gas.

As suggested you can try and add some sort of filter to the replacement air line . The best filters for that are the baffle types which is like a small mason jar with a couple brass fittings one hose inside the jar goes to the bottom a piece of foam/filter screen in between then a shorter hose out of the jar to the replacement air intake on the tank. This way you can see what's happening and eliminate much of the guess work.

Honda atvs had the same problem until they made the taller side wall mount fuel filter inside the fuel pump housing. The original round tea bag like filter at the bottom was asking for trouble.
 

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I would like to throw this out on this subject. In the past 20 years I have put 15,000 to 25,000 miles on 10 different snowmobiles and have never change a fuel filter. 95% of these miles was in the area north of the St Lawarence river in Quebec where I only see 10% ethonal displayed on one brand of gasoline and I avoid buying that brand. Is it possible that the fuel filter problem has something to do with a reaction of the ethanol added gas and the tank?
 

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i believe that the op is on to something with filtering question. i change mine every year cause : OEM filter are not see true ones ( for 1k that is ) and like one have posted earlier....gas station we stop by may have old installation or bad filtration system , lots can find its way in our tank. i like the dust questioning cause on my sled i have installed a filtering system for the air box to avoid the belt dust from getting in the intake. i noticed as i had to rebuild a motor that the isoflex in the bottom case was black colored from dust being sucked in from intake. i wonder though if the tank breather as enough sucking power to pull in much dust though... just a thought.... :rolleyes:
 

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For a time (before 2012) ethanol gas ate away at many dodge vehicle fuel pumps. What a mess.

In the interim we added stabilant to the gas the keep the ethonol gas homogenized.

I would like to throw this out on this subject. In the past 20 years I have put 15,000 to 25,000 miles on 10 different snowmobiles and have never change a fuel filter. 95% of these miles was in the area north of the St Lawarence river in Quebec where I only see 10% ethonal displayed on one brand of gasoline and I avoid buying that brand. Is it possible that the fuel filter problem has something to do with a reaction of the ethanol added gas and the tank?
 

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Mine on a 1200 Renegade X not sure what mileage was on before I purchased. I put on 3400kms this year with no issues. It was more of the needing to know how bad it will be when I pulled out kinda thought. My friend had issues with his 2019 900T cutting out and was related to the sock being near black with dirt. I was pleasantly surprised to see the color and how little dirt was trapped. It near needs to be linked to the tube screen on the intake being eliminated on the newer models. Inspected the end screen and nothing there. Checked the inside of the tank and nothing. No issues with float or pump.
 

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