Nothing wrong with dirt in the air box, thats what they do. Its dirt in the intake past the air box that has been a problem. I have an "08" with the "grumpy" mod and have never had dirt in the intake. Just bought a wrecked "10" I am rebuilding and it has signs of dirt in the intake and throttle body. It has a stinking oiled foamed UNI on it. No wonder.

 

the stock airboxes dont work to good.Your better off upgrading.

 

i never had problems with my stock box...but changed it anyways.... ump is what most get..

 

Mine was clean too after 600 or so miles of use in really dusty conditions. I believe it's a non-issue by 2011 MY. They made some changes to the setup last year. Likely similar this year.

 

I believe the change was made on the 2009 model. I think they changed the way the air box mounted which solved the problem. I have an '09 with stock airbox and clean/check it regularly. There has never been any sign of the dust getting past the paper filter in a thousand miles of use. I recently did a 100 mile ride that was VERY dusty (I was third in line with friends). When I got home, I opened up the airbox and there was a LOT of very fine dust in there and a LOT on the paper filter. Not any sign of any getting into the throttle body, however.

 

They did not change the way it mounts but rather they put a new boot on between the box and throttle body. This help for many people but the problem still exists for some with the new boot. 90% of the problem with the stock box is that it's mounted to the frame. The engine is on rubber mounts thus allowing it to move around. The boot going to the throttle body is the flex joint between the box and the engine. The boot will work itself loose and allow dirt to get through that connection. I have a 2010 rzr that I purchased with 150 miles on it. Here is what I found.

Dirt in the throttle body. Their was absolutely no dust getting past the filter. You can see in the photo that the boot is dirty only at the throttle body side. The filter end is clean and well greased.

When I dis-assembled everything all the clamps were tight and the boot appeared to be fully seated. You can only see the throttle body by taking the airbox out. I had looked through the airbox with a flashlight when I purchased it but could not see the dirt. The butterfly plate looked clean. Luckily my compression is perfect and I don't use any oil at all. I think the throttle body must have had a film of oil on it from the factory and it must have caught the dirt.

Take it for what it's worth, but I would never trust this "fixed" design. Buy a good transmission mounted airbox and have peace of mind. Otherwise you will constantly be worried and checking your box during and after every ride. Maybe you will be one of the lucky ones.... Or maybe you'll be rebuilding your top end in 3 or 4 hundred miles. IMO it's not a gamble worth taking. Buy a utv inc, Dfr, Ump, optiair, or other similar setup. The optiair one can be done for about a hundred bucks. Good luck.

 

I been asking this question about the 2011 model as well. I don't know what caused all the issues prior, but it worried the heck out of me, so I check the airbox out real frequently.

I have yet to find any trace of grit inside the intake. If there appears to be a lot of dirt in the airbox, I clean it out and use the shop vac on the filter element.

I have 1,000 miles on mine, and am on my third factory air filter, so far, so good.

 

i have a 2011 rzr 800 efi with less than 200 miles on it. the problem IMO is the location of the air intake. i do mostly wooded trail-riding and light mudding. im currently having to rebuild the motor because dirt in the intake is not covered by the extended warranty. the intake is right between the two rear tires in the worst possible spot. so if you ask me, i think the problem was not solved by polaris but rather "band-aided" :rm_thumbdown: i do not think they will own up to it and fix this design flaw so i would encourage anyone who does a lot of trail riding or any amount of mudding to break down and drop the cash on a good snorkel system to draw clean air. the dealer, addy polaris, quoted me for at least $4,000 as the minimum. im picking the rzr up this week and will get the motor apart and see what it will cost me. i am certain that the snorkel would be cheaper than any serious repair, even if you do the work yourself. That said, i love my rzr and the only thing id change about my experience is the addition of a snorkel and upgraded intake system before this breakdown. nothing beats the rzr on the trails and ill stand by that. im interested to see what others think and their experiences.
dont let any of this scare you off, it really is the best machine out there.

Seth,

 

i have a 2011 rzr 800 efi with less than 200 miles on it. the problem IMO is the location of the air intake. i do mostly wooded trail-riding and light mudding. im currently having to rebuild the motor because dirt in the intake is not covered by the extended warranty. the intake is right between the two rear tires in the worst possible spot. so if you ask me, i think the problem was not solved by polaris but rather "band-aided" ....

Seth,

Actually, the air intake is located between the passenger seats.

I'm a little confused by some of your statements....It should not matter where the intake is located, as long as the filter system is working.

You are the first post I've seen with dirt issues on a 2011, and with only 200 miles a blown engine? It's like you were riding without a filter at all....

 

the intake is the long oval opening that connects to the air filter box correct? on my bike it is slightly forward and above dead center between the two tires. i need to get my bike from the shop but i will post pictures when i do. the filter was intact and maintained. the dirt somehow got past it, which is why i tried getting the motor covered under my extended warranty. i understand it shouldnt get past the filter which is why im irritated about it and feel its a design flaw that if dirt can get past why did they put the intake between two tires which throw a lot of dust and mud. also i'm not always clear when i say things. they make sense to me =P but if you would like anything clarified feel free to ask and id be glad to try and explain what i tried saying before. once again im not bashing the machine, i love mine. i just think the intake location is a severe oversight by polaris

 

I don't think you are seeing things correctly. That long oval thing underneath the bed between the wheels is the PVT outlet. See page 116 of your owner's manual.

The air intake is between the passenger seats.

Was your air box dirty? Where did the dirt get past the filter system?

 

ah. i must apologize. that is my bad. i havent gotten to take a look at it. i was going by what the dealer told me that dirt has gotten through the intake past the airfilter. they showed me that there was dust in the "pvt outlet" that he called the intake and i didnt think to question them =\ he also put a flashlight over the sparkplug hole and said it shouldnt be black in there and that it meant dirt got in the motor and id need a new top end, crank, pistons etc.. how he knows that without taking it apart is beyond me. anyway. i do apologize for the mix up on my part. i see what you are saying and when i get the bike home i will investigate it myself. i cant apologize enough for the mistake. does the pvt outlet connect to the intake?

Seth,

 

You need to go get your machine and bring it to another dealer. This dealer is a complete idiot for confusing the PVT outlet with the intake.

Also, when you do get dirt into the engine, you will not need a new crank, or even new pistons (I don't think) you should just need to bore the cylinder and new rings. I don't think dirt in the engine causes the cylinders to be black, it causes them to be scored (not scorched!) so the cylinder walls will not be smooth, but scratched.

Did they do a compression and leak down test? What were the results?

Who is your extended warranty through?

What were the symptoms you brought the machine in for?

 

they did not do either of the tests. they may have been trying to get an easy buck off of me. i bought my warranty through polaris although i cant honestly say if they sell the warranty for another company. i brought the machine in because it had started having a hard time running. it would be running fine and then drop the rpms then fine again for a few seconds then drop. then before i made it up the drive, the rzr made a bang and stopped running and wouldnt start. they dealer did say that he couldnt get it to turn over. Ive built several derby cars and am fairly mechanically inclined so i was just going to bring it home and see what i could find after i get the tech manual. my buddies father has a machine shop so he can get good measurements taken for me where required.

Seth,

 

I have a 2011 800 RZR and just ordered a Uni filter. After reading some of the post I am wondering if I made a mistake and should I stay with OEM? After riding 200 miles on the Paiute Jamboree had lots of dust in air box and on outside of filter but intake was clean as a whistle.

 

What's confusing is that it seems most all the years have had some issue's with the intake and some not according to all the replys I ve read here and in other intake posts. I don't get it. How can some have the issue and some not have the issue. I'm thinking it may have something to do with the way the attachment of the intake to the throttle body. Maybe Polaris is just having an issue with the assembly points at the throttle body. Just install them all the same with the same torque. Don't they have a assembly model for this. I just don't get it.