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Its kind of like tooth paste with sand in it I was thinking it may get into places that it shouldn't and be difficult to get out.

The "CC Method" seems a little less aggressive.

OK, thanks for the info. I have never inspected a PWK that closely.

Thanks!

Valve lapping compound would be a reasonable choice, imo. But, it's a paste, and as such is going to get into places that may be hard to get it OUT of. The alternately wiping of the swab/paper doesn't have that problem.

Re: wet
Should be fairly easy to tell if the filter has fuel in it. That would come from a worn reed situation.

I don't see a response to the question, 'Are the vent lines plumbed to the airbox?'

Why would the vent lines be plumbed to the airbox?

Who would ever do that?

Hummmmm. I thought the same thing when I read it

Indawoods wrote:Why would the vent lines be plumbed to the airbox?

Who would ever do that?

Re-routing them to the airbox can help keep them from getting plugged up and help with deep water crossings. MSR sells a kit with extra hoses, a filter and junction T's to route the lines to your airbox.

Indawoods wrote:Why would the vent lines be plumbed to the airbox?

Who would ever do that?

Also keeps ice balls from cloging the ends riding in snow. I route them back down after winter, if I remember.

COOOOOLLLLLL.
That will be my stocking stuffer

Like morie said, that is an old trick that someone finally slapped into a package. You can just buy some fuel line and a pair of plastic T's from an auto parts store. I bought a pair of T's for $1.50. If you want a filter, then I assume some cheap foam could be used.

mattR, have you cut the ends of your vent lines at an angle? I read that it helps to prevent debris from getting clogged in the ends of the lines.

Makes sense... have never done it though.... I hate the cold!

Jason wrote:Like morie said, that is an old trick that someone finally slapped into a package. You can just buy some fuel line and a pair of plastic T's from an auto parts store. I bought a pair of T's for $1.50. If you want a filter, then I assume some cheap foam could be used.

mattR, have you cut the ends of your vent lines at an angle? I read that it helps to prevent debris from getting clogged in the ends of the lines.

Yes. I angle cut them anyway. The PC kit is nice, but I am cheap. I just used extra long lines and ran them under the seat an into the top of airbox. Zip tied to the frame. Worked fine.

On topic: When I had a problem with the carb pissing gas it was the little pin the float pivots on.

Routing all vent lines to air box will also create an slightly negative pressure within the fuel bowl which will lean out the carborator mixture a little. i.e. may need to rejet for the change.

FWIW - I don't know why you really need any foam on the vent lines. The vent lines exchange air without being filtered normally: I don't think the air box air is any dirty than the air down by the shock when your riding. Probably is more of a sales point - than a need IMO.

I was wondering about that, too. Do those lines draw air in or what?? I was thinking maybe if they were pointed up that they could suck dust, leaf particles, etc. in if they were pointed up.

I just slit the ends of mine so it has like a split end. I saw it done like that on my 00' YZ426F and YZ125.

Jason - As fuel is added to and consumed from the float bowl air is displaced. Changes in temperature and agitation causes the fuel to vaporize and if the vents did not exist the float bowl would at times be pressurized and at times under a slight vaccum when compared to atmospheric pressure.

The vent tubes allow for the displacement and replacement of air above the fuel level in the carb's float bowl. Hope this helps in understanding the importance of keeping the vents open.

It is a start on me figuring out why it goes BOG, BOG, BOG when I rode through footpeg high water before. I don't/didn't have the T-ed off, run high, style lines, just the stock configuration.

So, basically it is a pressure equalization measure??

My thoughts on the bogging when you go through water is: the pipe cools off so fast the engine is not getting the hot pipe effects and thus it acts similar to lean jetting.

I've been told that if you turn on the choke prior to entering a deep water crossing that your engine will respond better. Been going to try it but have never remembered to filp the choke on prior to entering a deep stream crossing. I usually a little nervous and just looking for 'a line" through the stream. Therefore, don't know if it works or not. On stream crossings though, I do rev the engine more and slip the clutch a little because it is unnerving to me when much of the engine sounds are deminished do to being under water.

My bikes are stripped down right now, but when I get one put back together, I am going to stick the hose ends in a cup of water and see what happens.

Excellent idea Jason - let us know what you discover. I know I've thought about this a time or two when I've read Q&A in the dirt bike mags over the years.

My understanding - The basic theory is that as the fuel is used out of the float bowl air enters through the vent hoses to replace the spent fuel space. Float drops opening the gas supply needle and the float bowl refills displacing some air out the vent line......over and over and over

Blockage of the vents with water or mud reduces the atomospheric pressure within the float bowl. When the atmospheric pressure is reduced within the float bowl - the venturi created negative pressure created by air passing over the carb's nozzle can not draw enough fuel into the carb's nozzle: causing the engine to run lean and eventually stall.

FWIW/IMO - Dirt bike magazines articles or Q/As for the most part indicate the fuel bowl goes dry. I don't believe this is what happens. The float should still open and fill the bowl. What you don't have is adequate atmospheric pressure on the fuel: The venturi does not have adequate pressure differential (compared to the pressure within the fuel bowl) to draw out the fuel. Thus the bike starves for fuel even with a full carb bowl.

I'm interested to read what you find (how far will the water rise in the vent tubes prior to your engine stalling.) Also of interest, to me anyway, is a confirmation of whether or not any fuel is in the carb's bowl when engine stalls. Isolate fuel supply just as engine stalls and check carb's bowl for level of gas if your so inclined.

You folks are differentiating between vent tubes and overflow tube(s)?