UNI filter lets sand threw.

[bandit390]

Yep. I took my carb/etc off today and come to find out that there is sand in my air box boot and carb. I use a uni, which is not old and was oiled. Also, the reason I took my carb/etc off is because I sunk my 400 in a sandy river a couple days ago and wanted to clean it up. So maybe that is the reason sand got threw? I hope it does not let it threw all the time. There was not that much sand in there, but there was enough, that I could tell.

Any other people with UNI's have this problem or just mine?

[RAPTORAZ]

I've used Uni's for years. And mostly dune ride. Sounds like you either missed a spot when you oiled it or you didn't have it on tight.

[White_Knuckles]

Not good, dump your oil twice. No quality foam filter will pass sand or larger particles under normal operation. Water saturation might swell the foam cells but the density is still too much to pass any viewable amount.

If it was a submarine for an extended time and then not throughly inspected you could of missed it. A loose clamp or boot?
Check everything and reuse the filter. :D

[KY Woods Rider]

Originally posted by bandit390
Also, the reason I took my carb/etc off is because I sunk my 400 in a sandy river a couple days ago and wanted to clean it up. So maybe that is the reason sand got threw?


Yep, my bet is that the sand got in when you took it swimming. Many types of filter oil don't resist water very well, and the force of the water rushing in will keep the oil from holding the dirt as it passes through. A simple splashing won't let dirt in, but a complete submarine act can.

As the other posters have said, check all the clamps, the air boot, check the filter for tears or holes (especially around the glue seams), and make sure you oil it properly. A foam filter is probably the best filter available for stopping dirt and sand, but it must be properly oiled with a quality filter oil to work. A foam filter that has un-oiled areas will pass dirt fairly easily.

I've used UNI filters for years, as well as several other brands of foam filters, and I've never had any problems with them passing any dirt, sand, etc; but I never use my quad as a boat either. Just be sure to use a good oil and get the filter completely covered. You don't need to leave the filter saturated with oil, just make sure there aren't any dry spots.

[thejeepdude]

I'm not saying you did this, but many people on this board have mentioned they are using everything from motor oil to gear oil to K&N oil on their foam filters. This is NOT the same as using a good foam filter oil. The foam filter oil I use is super sticky, and semi-dries even to the point it won't drip or run if the filter is "over-oiled". My buddy had a bunch of oil in the bottom of his airbox when we put his K&N in, and he said "I just oiled it, so that's the extra oil". I knew right then it was the wrong oil. Anyways, just thought I'd mention that because a lot of people here seem to think running regular type oils is just as good... NOPE!!

[RiPPiNiTuP7]

I run the Uni Filter and use their oil as well...my boot is always spotless. Must of done something wrong.

i have a uni air filter but no oil...how often should I oil it & what kind of homemade oil can I use?

[KY Woods Rider]

Originally posted by Crazy400exMan
i have a uni air filter but no oil...how often should I oil it & what kind of homemade oil can I use?

The filter should be oiled after each cleaning. Just clean the filter, let it dry completely, and then oil it. The only oil that I'm willing to use on my foam filters is oil made specifically for foam air filters; I prefer PJ1's "Super Tacky" foam air filter oil, but any of the major brands will work pretty well. Any type of oil would be better than nothing, but anything other than a quality foam air filter oil will end up as a puddle in the bottom of your airbox. Even though it costs more, using a quality filter oil is cheap insurance to make sure the oil stays in the filter and stops dirt from getting into the motor. However, if you absolutely insist on using a commonly available oil, then a heavy weight of gear oil will work better than motor oil.

[thejeepdude]

It's the life of your engine we're talking about here. Saving 5 bucks on a bottle of oil that will last you at least 4-5 cleanings is STOOOOPID! :confused2: I used to use gear oil myself until someone showed me how worthless it is on a filter. It will work partially... for a little while... but so what? Would you put some corn oil in your engine? Or transmission fluid in your fried chicken? I didn't think so. Get some FOAM FILTER OIL. Massage it in thoroughly, let it sit, reinstall, and have peace of mind that you're not sucking dirt into your engine!

[airheadedduner]

One thing that people forget is you need to grease the flange that your filter clamps to. Sand can slip through there no matter how tight you clamp it.

[thejeepdude]

I would disagree with the last statement. You don't need grease on your flange. If anything, that will make it more likely to fall off. That's what happened to my stock filter when the last owner greased the flange. When I got my new UNI, I decided to clean the flange with solvent, and it stays put, and there's no way any sand is coming through a nice clean 1/2 wide rubber seal. Mine is always suoer clean inside the intake tube every time I check it. By the way, after I decided to do this, I notice it specifically said in the filter instructions to use a solvent to clean the off any filter oil that got on the flange. Not a flame, glad your way works for you, but I'll stick with the clean method. :)

[wheeltrax]

I have a UNI on my quad also, and so far have not had any problem what so ever. I also have had a K&N and had no problems with anything going through it either. I just make sure its well cleaned and oiled all the time. It could have been when you had the quad swimming.