Hey everyone, just bought my first quad last weekend and im having a fuel issues. Wondering if anyone with polaris 500 experience could tell me whats wrong here



As you can see its leaking fuel out of the bottom of the carb, and it almost looks like a hose is missing... Should there be a hose on that nub that the fuel is leaking from? Or do i just need to tighten it?

I've also been having a few carb related issues (possibly because of this?)
It wouldnt idle until i adjusted the throttle cable
Bogs down under throttle (unless i turn the fuel cutoff switch to the off position the night before)

Im not too familiar with these little motors, but one thing i am suspecting is that the carb float may be stuck in the open throttle position which is just giving the machine way too much fuel

Any help or information would be really appreciated!

 

Yes the hose should be longer on the carb bowl. This was a hard carb to keep from leaking just the because of the way the float and needle and seat were designed. They're held in place by the float bowl itself and the float must be adjusted properly or will leak.I had a hard time myself on these carbs. I'd install a new carb kit.http://www.ebay.com/itm/Polaris-Sportsman-500-2003-2004-2005-Carb-Carburetor-Kit-/261252497842?pt=Motors_ATV_Parts_Accessories&hash=item3cd3dcc1b2&vxp=mtr Plus look at this post on the Mikuni BST40 carb. Similar to yours,but used on a KTM. Look especially on how to adjust the float height!The BST-40 Bible - ADVrider

 

I really appreciate your wealth of knowledge OPT! I have been thinking about a carb rebuild so i did just place an order on that kit. I have never rebuilt a carbuerator before.. where could i find some good step by step instructions?

Now in the meantime what should i do to minimize the leak (short of parking the quad). You said the hose should be longer on the carb bowl ...is it just a drain hose or what does the other end attach to?

 

It's an over flow/drain hose and doesn't hook to any thing else. Just get a length a of hose at an auto store 3/16" diameter,enough to go past the engine skid plate. If it continues to leak at least it's not on the engine which is not too good. Just look over the link I showed on the carb. You don't have to do the mods he did,but it shows you the basics on this carb on rebuild,plus float height adjustment. I wouldn't mess with the carb until you get the kit.. Plus since it's bogging down ,I'd do an oil and filter change. I can imagine it probably has gas in the oil if it's doing this..

 

I was kind of worried about the gas in the oil you mentioned so i checked the dip stick and sure enough.. Seen two little bubbles on the stick. I hope that the small about of bubbles means that there isn't much gas in there. But i like to error on the side of caution so i'll try to avoid driving it until after i rebuild the carb and then give it a fresh oil change

Im not to familiar with these 500 singles but i remember the old carbed v8 engines didnt like to last long after the cylinder walls got soaked in fuel. What's the best (easiest) way to check the extent of the damage on these motors?

 

They're pretty tough engines.When you get the carb kit installed and running right,drain the remote oil tank.After the tank has drained,crank the engine up for ten seconds ONLY,then kill it.The oil from the sump(about 8 ounces) will drain into and out of the remote tank. Remove the old filter,replace with a new one and two quarts of synthetic oil,0w40,5w40,or 5w50 range.My own preference is Rotella T6 5w40 synthetic. Good oil and usually cheaper than Mobil 1,Amsoil,etc.

 

Alright so I got my carb kit in the mail yesterday. With out wasting much time i took the quad apart, pulled the carbuerator and started following the the steps in that writeup. To my suprise, everything looked pretty clean and came apart fairly easily... Until i tried removing the slide.

Laramie_LC4 says, in his writeup, that all you need to do is push the needle jet in and the slide will come out. For me the needle jet came out by its self (with some forcefull persuation). Leaving me to understand that the slide is stuck.

Here are a few pictures to help explain:



You'll notice in the second image that the slide isnt flush with carbuerators inner wall. Would this confirm that it is stuck open?

Could anyone tell me if this is consistant with the leaking carb problem? And if im on the right track what is the best (safest) way to get that slide un stuck without harming the carb?

 

Spray penetrating oil(Wd 40, PB Blaster) around the the top of the slide,let it sit awhile to soak through the sticky varnish, then you can use a flat blade screw driver to gently pry it up from the bottom. Being stuck sure wouldn't help on running,but the float level is the most important thing after you get everything cleaned up and back together as far as gas overflowing from the bowl.

 

Thanks for the quick reply OPT, sure enough WD40 did the trick!

Now when I took the top end apart the needle came out like nothing was wrong. Personally I would have expected it to be a little more difficult if it was the problem.

I guess I'll just have to wait and see how it runs when i put it back together!

 

Well..... after some well spent blood sweat and beers I got the old 500 to sing in tune once again!

I think the worst part was disconnecting the choke cable ....I had to sacrifice a new 12 mil wrench to the grinding gods! But after removing/ installing the carb twice I'm pretty confident that I could do it with my eyes closed.