anyone have problems with getting junk in carb even with fuel filter

 

Got a picture or better discription?
It depends on what it is. Shouldnt be rust, because theres no steel in the system.
If its dirt, then a better quality filter should catch it.
If its the hard deposits, left in the float bowl and on the jets, thats from evaporation. If thats the case, then make sure you turn the gas to off, when the quad isnt running, and drain the float bowl if its gonna sit for more than a week. That should prevent the varnish and hard deposits.
What kind of junk is it?

 

it almost looks like brass or copper,probably sand that got hot/gas.the way the air filter sits in the box is a little sketchy it just sits in a groove.i saw someone mention a proflow air box but it doesn't appear that they make it for kodiak 450 '05 also a meukin carb was suggested. what's your opinion?

 

Sounds like sand to me. If it were mine, id pull the tank off, and drain the gas out of it, thru a coffee filter, and then use it in the lawn mower. Then id flush the tank with warm water, and let it dry. Putting it back together, make sure you use a new, good quality inline filter...and it should be good for a long time.
If it were mine, id leave it totally stock. Theres nothing wrong or inferior about the carb. Im thinking the air box is the same on an 05 as my 04, but I could be wrong. it doesnt matter on mine if the lid seals good or not, the filter should trap all the grit, if its properly oiled. Do you have grease around the rubber, where the filter connects to the tube? When you wash the filter, does there seem to be alot of grit coming out of it?
You can spend alot of money on a new carb, and there wont be alot of difference in performance, and itll still plug if theres dirt in the gas.
Just my 2 cents.
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