Well..... I don't know what I did, or didn't do the first time but after taking it back apart and going through it again, it starts right up without even choking it and purrs like a kitten. Thanks y'all. I have another question as far as coolant, I'll ask but please let me know if I need to start another thread.  The coolant reservoir is reading on the Low mark, do I add coolant to the reservoir or in the radiator cap directly? Again, excuse my ignorance but this is my first time on a water cooled Quad...

I appreciate the responses y'all, yes, the plastic thumb screw dial thingy is what y'all mentioned, it is to adjust idle. I wasn't sure what to call it, lol. Anyhow, I didn't see any splits or tears on the intake boot and also double checked the connection was sealed. I even sprayed a quick burst of carb cleaner on the connections and it didn't speed up the engine. When I had it apart I did remove every jet as well as the emulsion tube, the emulsion tube and the pilot jet were both partially clogged and I cleaned everything. As far as the mixture screw, apparently someone has messed with it at some point because the cap has been removed, is there a special tool required to adjust that and what is a good starting point as far as setting it? As far as I know there haven't been any mods to the machine but I will be talking to the owner this evening.

Howdy y'all, I'm trying to fix a neighbors 2015 Brute Force 300. Came in with hard to start and won't idle except on choke issue. I pulled the carb and found the pilot jet as well as the emulsion tube partially clogged. Cleaned up everything, put it back together, still having issues...  It will start right up on choke and will also start off choke if you give it just a touch of throttle but it absolutely will not idle unless it's choked just a touch. Also, excuse my ignorance but I'm assuming the "dial" thingy attached to the carb that turns in and out is for setting idle?? 

Really good forum....   Still learning in La Vergne, TN

I've got a hole in my air on my 97 Polaris 300 Xpress approximately 1.75" x .75".. 

I have searched the Ole internet and found a ton of conflicting answers as far as how to seal it properly. It is directly next to the carb intake port and there is a ton of suction. Any advice would be greatly appreciated...

Ok, the parts fiche for my machine calls for the 520 o ring, 86 link which is the chain that was on it so I'm good on that. 

As far as sprockets,, it calls for 12t/36t but this machine has 12t/38t sprockets. What happens if I go back to the 36t rear sprocket? 

I have tried googling the answer only to confuse myself, unless I'm backwards, the extra 2 teeth on the rear sprockets helps on low end ??

1 hour ago, davefrombc said:

The higher tensile strength chain would be  best  and definitely O ring chain  will last longer  unlubed. I  saw a quote of the 8700 tensile strength for the OEM  chain.
 In   my search I  came across a listing of  520  O-ring chain with a tensile  strength of 8200 in an online listing by the US  Walmart  (.com) that as long as it is the right width for  the sprockets  should  fit.  As long as you're  not beating that quad to the max the slightly lower strength chains should do the job. You'd  have to  count the links ( pitches)   to  order the chain and confirm  price.
I hope that helps.

Yessir, it helps a lot. Thank you..  Just took the old chain off and found a missing tooth on the front sprocket so it looks like I'm going to go ahead and replace both sprockets as well.

The OEM o-ring chain for my '97 Polaris Xpress 300 is $130+ while other brands run from $50 up to $80 with varying tensile strengths from 5000 to 8700. I would assume a higher tensile strength would be better but I don't know the tensile strength rating on the OEM chain. I usually always try to run OEM on everything but if I can save a little money it would be nice, if I'm looking it up correctly it takes the chain listed below but I have no idea what the ORD4 means...

CHAIN-520 ORD4,O-RING,86 PTCH

3221193-086

Thank you sir, that's great information. I think I'm at the point of having to diagnose another problem I'm having with this carb but I'm gonna probably overthink it first before posting it to try to figure it out in my head..

1 hour ago, Mech said:

I'd leave the hat on the shelf for now.

It's possible you had two problems, which can really confuse the issue.

Well done for getting to the bottom of it.

Lol..  I'm definitely not counting my chickens yet but it's doing very well at the moment. 

Still have a list of things to do to it otherwise but it's running and idling very well. I finally got to ride it for the first time without it bogging or quitting.

Credit goes to this forum and those that replied, it was the service manual download that finally set everything in. I've certainly learned a lot but have much more to learn. The flooding issue, which has tested me for an unacceptable amount of time is solved though. 

I'm sure I'll be making separate posts with questions on other topics but maybe this thread will help someone like me someday. 

This was a double post so I edited it out, I don't know how to remove it. Sorry

Well y'all, I feel like a complete idiot. I had the choke all out of whack and that was my issue the entire time.

I didn't realize the choke had a half setting and thought that was full choke, Long story short, it starts right up, idles good, and has about 60% less smoke from the exhaust. I ordered myself a dunce hat, it should be here tomorrow..

Thanks Mech, I just went ahead and ordered a few OEM ones for the time being. Once I see exactly what they are maybe I can direct match them if the need ever arises.

I figure since the old one came out in pieces it would be hard to match anyhow. I may as well get what it calls for after all I've put myself through, lol.

I'm not counting my chickens until I get it back together but it makes sense to me now. I will definitely do the tilt test. 

Big thanks to everyone, I'll update when I get it back together.  Fingers crossed !!

On 2/22/2022 at 11:03 PM, Mech said:

That metal washer under the float needle seat might not be sealing. If the surface was made to have a rubber ring it may not seal with the metal washer. It might be changing the float level too.

After this info as well as the info in the post Imade above this one, I took the carb back off this morning to compare the "packing" to the washer. 

It couldn't be more obvious, the hole that the needle seat screws into has a small groove inside that sits slightly lower than the outer ridge.

The washer sits on the outer ridge where as the packing should sit down inside on the groove. You can see the what I'm referring to in the pic. I'm 95% sure that is my issue. I feel like an idiot for not noticing this sooner.

Now I have to order a few so I have extras and wait 4 or 5 days for it. It seems it's not a typical "o ring" because even the ones that small seem thicker unless someone knows something else I don't..

The parts fiche for the Express 300 shows 2 different carbs, one shows a needle valve washer (part #3130047) and the other shows what they're calling a needle valve packing (part # 3130017)

Considering mine originally did not have the washer, I can only assume it takes the latter. I'm going to have to order one and wait forever for it but I'm hoping and praying that is my issue.

49 minutes ago, Mech said:

Have you checked the float actually does float ?

As has been said, you need to be sure the float works and isn't leaking between the float needle seat and carby body. A simple test is to take the carby off and tip it up on it's side while you blow through the fuel inlet, then slowly tilt the carby till it's level and the needle should seal against your blowing. It should actually stop your blowing when the float starts dangling down against the needle, it doesn't have to be totally flat. If you tilt it so the float swings away from the needle, then swing it so the float will be dangling but against the needle, it should stop the flow then.  It's a good idea to do that test whenever you've had a carby apart. Sometimes the floats get jammed down by the needle dropping too far. Rare, but it does happen.

Honestly the way you described it, I'm not positive. I do know the "floats" float with fuel in the bowl but are they actually raising the needle assembly when it's put together, again I can't say for sure.

I will check with the method you described. With all of y'alls responses I definitely feel like I'm narrowing things down. Much appreciated to you all..

47 minutes ago, Mech said:

If the choke is a plunger type, they only operate when the throttle is closed, or near closed. When the throttle's open they don't have enough vacuum to lift the fuel. I'd pull the plunger and check it's still got it's rubber seat/seal.

If you turn the fuel tap off and start it, what does it do ? If you turn the fuel on and off enough to keep the carby just full enough to run, does it still flood ?

It is the plunger type, where exactly would the rubber seat/seal be? There's a plastic cylinder/plunger that goes into the choke hole, if you look down into the plunger hole there is nothing but a smaller hole in the bottom. 

I've not tried that process with the fuel valve so I'm not sure. 

2 hours ago, spock58 said:

First thing with flooding that is suspected is the needle & seat - it could be the problem still. Since it was replaced, did you install a new gasket (or o-ring) on the seat?

It's important to get the proper size n&s since there are different styles/sizes available; gravity vs. fuel pump fed. 

Considering this is the first carb of this type I have dealt with and the po obviously left at least one piece out, I'm not sure.

The seat I took out of it had a tiny rubber o ring that sealed(?) when it was threaded into the carb, it broke in half when I took it out, the new one has an equivalent size metal washer. I do know the needle and seat are identical to the ones that came out of it otherwise. 

The kit came with the machine and I just assumed it was correct. (Possibly a bad assumption?) 

This thing is definitely testing my patience. It's definitely a flooding issue, if I drain the crankcase and leave the drain plug out, it starts first push of the button and idles just enough to keep it running for maybe 15 to 20 seconds. 

When I put the drain plug back in, it doesn't want to start and won't idle. When I take the drain plug right back out, it has gas in it again. 

Petcock is new and is working fine, it's only flooding when I try to start it and keep it running that it fills the crankcase. 

I guess that's my next route, went through the carb again yesterday. I set the floats from what sparce info I could find on YouTube and still have the same issue. Definitely a learning experience...

I appreciate the info, I should be able to mess with it again sometime tomorrow. 

This is the first time I've ever seen the floats made into the bowl and it's thrown me for a loop for whatever reason but I'm not giving up.

I promise I'm not a mechanical moron but this thing....  

Thanks everyone for your input, I'll be using it all. Got carb back on this morning, no difference. 

Still starts only with throttle held wide open and will not idle. Pulled the crankcase drain bolt and drained about 3 bottle caps of gas. I left the drain bolt out and went to crank it just to see if everything drained, it started right up on its own and idled extremely low off just the gas in the carb bowl.

Put the drain plug back in, hooked up a fuel source, and again it would not start without holding the throttle wide open and would not idle. 

Pulled the drain plug again and got about a cap full of gas. The carb is also shooting a mist of gas out the back of the carb when I keep it running. 

Took the carb back apart today and literally cleaned every single piece and every passage, I'm more confident now than the first time I went through it. The pilot jet has a hair thin obstruction inside that would not come out, not exactly sure what it is but I replaced it with the new pilot jet. First time I did not take the slide apart and pull the jet needle, when I pulled it today I discovered the plastic washer under the clip was not there. I'm not sure what that affects exactly but I put the new one on it from the kit. Also found the new check valve on the carb overflow tube was clogged, is that check valve necessary? 

Is 100 psi acceptable on the compression test? As far as setting float level, I can't download any manuals until I get to 10 posts but I'm hoping I at least have it in the ballpark. I've checked and not found any manifold leaks. I'll be getting it ready to start in the morning and see what happens....

Alright y'all, compression check shows 100 psi and it holds it. (tested with carb both on and off the machine) As mentioned, it has been bored .30 over, it was bored before I got it and supposedly didn't have a lot of ride time afterwards but I can't say how fresh it is. Seems it should be a bit higher from what I've researched but I really don't have a clue. As far as float adjustment info on this forum, I haven't found it yet but also haven't had a lot of time to look. As far as the jet needle, it appears to be factory 169 and is set on the 3rd slot from the top (as it was when I got the machine). Pilot jet is factory #40, and main jet is factory #155

Fuel was mixed by me and is fresh, also replaced Fuel lines, tank was empty when I got it. 

I have not checked compression but will definitely do that. 

I've checked the Intake connection and found no air leaks. I'll recheck the idle mixture screw because it's definitely not changing anything and I'll see if I can find the download for the float adjustment. Thank you, this thing is testing my patience.