2004 Honda rancher TRX 350 4 x 4 carburetor leaking

[Johnwing5 5]

I’m having a problem with my carburetor on my Honda 350 so I took the carburetor out rebuilt it cleaned it spotless put it back in it’s still leaking. I did this three or four times check the float checked the float pin. Still leaking. After taking it out cleaning it five or six times I decided to buy a brand new carburetor it’s a Honda OEM carburetor. Put it back in and guess what it’s still leaks. So I took the new carburetor out checked it out cleaned it up put it back together put it back in and it stopped leaking for a day. So took the carburetor out cleaned it again check the float checked everything. Now it’s leaking like a sieve. I am at a loss I’ve tried tapping on the carburetor to see if the float stuck I have taken the gas cap off to see if there was venting. Now I’m really at a loss we have a camping trip in two weeks and I can’t get it to stop leaking gas it even leaks gas when it’s running. Any thoughts anything I didn’t do. Please help

[Fishfiles 20,145]

I would think , you didn't clean the tank , petcock , fuel lines an reintroduced trash into into the carb you just  cleaned

[Johnwing5 5]

Thank you I’ll try that. I will let you know 

[AKATV 820]

I would like to second Fish's reply on this, as I just went thru the same thing last April-

I had an 02 TRX350 Rancher that was dumping fuel out the overflow and I had cleaned the carb and blew out fuel inlet a couple times and it would clear up for awhile -then start doing it again

I would keep finding little bits of sandy type sediment in the bowl and around needle seat

Ended up flushing tank and and checking the filter screens on petcock and they were OK, but when I disassembled petcock, it had ALL kinds of sediment bits and crud in it

After I cleaned it out, I put a clear glass jar under the end of hose that goes to carb, and with gas in the tank, I put a bit of compressed air in thru the gas cap vent hole

(which i thought was only a one way) and then cycled the petcock from off- to on- to reserve a couple times and gas and even more crud shot out under pressure into the jar

I scrubbed out the fuel line with coat hanger with a small bit of cloth around the tip-LOTS of crud in there too...

I did that a few times till it all came out clean and have not had a problem since and its been over 3 months

I would think that the slight bit of water in the tank that comes from condensation, fueling in the rain etc...settles down bottom and gets down into and sits in petcock over winter etc and mineralizes in the petcock and hose lines and causes problems with buildup  Anyone who has seen all the white calcified mineralization in a carb float bowl knows what I mean -same stuff

Good reason to drain lines and bowl at end of Season or when not used for long periods

I know these Rancher 350s have been known to have leaking issues with the needles, but what I have found on the ones i have looked at has pretty much been like the the above in all cases

Also, on that note -be sure to turn your fuel OFF if you put it in garage etc-

I returned to my attached garage after pulling wheeler in to find the whole floor under the ATV soaked with gas due to a needle valve/ leaking out overflow and  dreaded the thought if I had gone in for the night and the furnace kicked on.............it.would have kicked on with a vengence one last time..

Thankfully being Winter i keep the garage at 40 degrees and that helped a bit with fumes and volatility that time. -So be careful with that

I got to the point of even clamping off lines on the vacuum controlled petcocks when i bring them in just in case

Better yet- keeping them in the shed or outside

Anyway good luck and let us know what you find out

Edited July 18, 2020 by AKATV

[slowindown 494]

Another little note.  As to the brass seat where the float valve seals off the flow, I take a q-tip swab and wrap it with very fine steel wool so that I have a steel wool Q-tip.  I slide that into the seat area and spin it.  Depending on how dirty, I may use one, two or three of those modified Q-tips.

[Johnwing5 5]

Well here is an update on the carburetor I used all of your suggestions. Can’t believe after putting it all back together and running it a few times it doesn’t leak. Well it makes sense (now) I probably didn’t need the new carburetor well now I have a spare. I should have gotten on this form years ago save myself a lot of time and money.  From now on when I rebuild a carburetor I will make sure to clean the fuel tank, petcock, fuel lines, and clean the carburetor bowl really good q tips work great. By the way I have watched every you tube video believe me there are a ton not one of them suggested what you all said. I can’t thank you enough for taking your time to help me. I also hope this post will help other people with the same problem (follow their directions it works) Thanks again

[julian Lindley 4]

This conversation, particularly Fish’s was an eye opener to me. What I believe occurs is that petrol is left in the fuel tank for long periods without being renewed. The chemistry of fuel has changed considerably in recent years with bio - ethanol being added and sulphur removed. Fuel degrades more quickly too. I I have noticed the tiny particles in the tank fuel cock and in the carb’s float chamber, they can stick to the Viton coated carb’ needle valve and cause overflow of its float chamber. It is hard to believe that the float settings would change, or indeed that the needle seat would be damaged. The fuel tank is frustrating to clean out as it is difficult to flush from its filling point. I spent a half day doing it using a funnel with a removable fine mesh filter into a large bucket, reusing the fuel after passing it through the funnel filter back into the tank and cleaning the filter each time in the process. A large amount of granular material in the petrol on/off cock demanded I replace it, particularly as it did not entirely seal, dripping every 5 seconds when the valve was turned to off, whatever the fuel head. I imagine that it would eventually equalise in pressure with the head of fuel in the fuel tank - more load on the float needle. So in conclusion I believe Fish is correct. Clean all of the components or replace and all should be well. I decided to purchase an OEM carburettor aswell.

 

 

[julian Lindley 4]

One final point, It seems likely that oxidation of the aluminium that the petrol tap is made from is contributing to the problem. Our machines are not young, and the taps have been immersed for a good while. My suggestion is to replace the tap also as its design is sealed. The large filter over also degrades and becomes brittle and fragile. Good luck from the UK!

[Fishfiles 20,145]

1 hour ago, julian Lindley said:

One final point, It seems likely that oxidation of the aluminium that the petrol tap is made from is contributing to the problem. Our machines are not young, and the taps have been immersed for a good while. My suggestion is to replace the tap also as its design is sealed. The large filter over also degrades and becomes brittle and fragile. Good luck from the UK!

 

Hi Julian , love the way you guys from the other side of the pond talk , I am starting to learn a bit , would guess the petrol tap is the petcock , you are right most are sealed and not serviceable , but I have seen some members drill out the rivets , then tap the rivet holes to accept screws , they were able to get a new oring , @Goober  is one that does that ---------- with our older atvs , parts are getting harder to get , they do offer aftermarket " pee-taps" LOL , but they  are cheaply made using  cheap quality al'you'min'u'mun