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As per title, is this a symptom of a stuck float? I can crack the bowl and see if it moves freely, but do I have to or is this normal if petcock is not closed? Fuel was dripping out air filter.
 

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If you have a kick starter, without the ignition on try and slowly turn the motor. No kickstarter... put it in third and turn the engine. You can do both of these with the spark plug out if you feel a lot of pressure and fuel got into your engine. A good way to avoid Hydrolock.
 

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As per title, is this a symptom of a stuck float? .........
Yes, precisely. Or a leaking float needle seat. If gas was dripping out the airbox, it was also likely dripping into the cylinder, so you will need to check for gas smell at the oil filler neck...probably you should assume the oil is contaminated with a substantial amount of gas...not good for bearings.....AT ALL! :eek:

If all the above is normal, the petcock can be left on for long periods, AS LONG AS THE BIKE IS NOT TRAILERED!
 

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Check the oil to make sure it doesn't have gas in it. If it does change it out. The engine could explode if a spark were to ignite trapped vapors in the crankcase. Sometimes just a small bit of trash can hold a needle open and cause it to leak. I always shut the petcock off because this can possibly happen at any time. As others stated your seat and needle could be worn.
 

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As per title, is this a symptom of a stuck float? I can crack the bowl and see if it moves freely, but do I have to or is this normal if petcock is not closed? Fuel was dripping out air filter.
I had this problem and it was an o-ring. See red arrow -- I replaced it and all was well.

Float1.jpg

Or it could be the needle.........

P4160950.JPG
 

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I had this same issue happen when I trailered my TW from Sacramento to San Diego. Before I left I made sure the petcock valve was set to off and I ran all the fuel out of the carburator. When I got to San Diego I opened the petcock valve and fuel started overflowing from the carburator. I read on line that the float might be stuck so I hit the carb bowl with a ratchet handle a couple of times. I then turned the petcock valve to the on position and everything worked fine. It's an easy way to attempt a repair. Give it a shot.
 

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Rocky - your comment on trailering may help me - I am a new TW200 owner and noticed today while trailering that fuel was dripping out of the float bowl drain hose. I stopped to check the tie down and noticed a drip that stopped soon after I pulled over. The drain screw was tight and the fuel petcock was in the on position. Appears to only drip when trailering - not when stopped or riding. Bike runs good before and after. What gives?
 

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Rocky - your comment on trailering may help me - I am a new TW200 owner and noticed today while trailering that fuel was dripping out of the float bowl drain hose. I stopped to check the tie down and noticed a drip that stopped soon after I pulled over. The drain screw was tight and the fuel petcock was in the on position. Appears to only drip when trailering - not when stopped or riding. Bike runs good before and after. What gives?
Hey OTD,

in Rocky's brief absence, let me see if I can answer your question...

Why when trailering? Because of the motion. The back and forth and the bouncing and jarring make your float, and hence your float valve, bounce and dance. If the petcock is not OFF, the movement allows the valve to keep opening letting more and more fuel in. Make sense?

So, the drain hose is also a overflow relief hose. If your float bowl gets too much fuel in it, this is the overflow, and works in the same way your bathtub works. A safe method is provided to get rid of that extra fuel. Let's think about the bathtub for a sec, what were to happen if your overflow gets plugged or broken in some way and the water does not shut off? Nothing good, right?! Same with your carb. What if your overflow gets blocked or can't take the amount of excess fuel coming into the carb? Where would the fuel go? Hopefully it goes out of the overflow tube, but if not it will get forced out of the jets and carb orifices, then maybe out of the intake back into the airbox. Or, it will head towards the motor. If the intake valve is open, it will start filling up the cylinder. This may cause a hydrolock situation. Then, or if the valve isn't open, it'll find its way into the oil passages settling down into the bottom end of the motor with the oil. This is all bad. This is why it is VERY important to turn your petcock to the OFF position. Especially, when trailering, but a good habit to do always.

So, if you left your petcock open when trailering, do like Rocky says...check your airbox for fuel, then open your oil fill and smell for gasoline in your crankcase. Check your tank for any amount of perceived lost fuel. If you at all suspect that fuel got into the crankcase, change your oil. It's only a quart. Lesson learned, start turning off your petcock.
 

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Thanks IRPPCER - makes sense - was thinking the float would be bouncing during trailering and causing fuel to come in but did not know that there is an overflow relief that dumps into the hose that bypasses the bowl drain plug. Good to know!! Fuel loss was minimal and bike still runs great but will do a crankcase and oil check manana.
 

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Discussion Starter #13
So, engine started but took 30-40 kickstarts (no electric start on mine anymore). Bike ran fine once it fired up. Happened a second time a week later, I left petcock open, fuel on floor. Same problem starting. Then ran fine.

Twice now when out on a longer ride, I've stopped and turned off engine. Pulled out maps, etc. on a short brake. Didn't turn off petcock. When I went to kickstart, wouldn't turn over and sounded flooded. Had to roll start.

Oil appears normal coloration. Carb was cleaned 1 mo ago by prior owner, this is a 2014. If float or needle leaking, wouldn't fuel be coming out bowl drain hose as well as the air filter?
 

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I think you’re missing the point

1/ the petcock on a TW is gravity fed – no diaphragm – if you turn it off, it shouldn’t let fuel through

2/ if the needle seats correctly, it will also block flow

So – there is apparently something wrong with your carb. When trailering the TW, sure, you should turn the petcock to the off position, this is also a good idea when parked up. From the circumstances you describe though, I’d take a good look inside the carb.

The very fact the PO took it apart indicates a problem, and you only have his word for it that he found it and fixed it.

The hot start issue may be down to a number of issues, so you need to look at the float level, the needle seating etc, and the main (and idle) jet. For the cost involved, I would recommend replacing parts where possible, as eye-balling doesn’t always tell you what’s going on in there.

Trailering aside, set up correctly, these bikes are pretty bullet proof – yours is not, ergo, it is not set up correctly

Something is wrong (or at least not quite right) inside your carb …….
 

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So, engine started but took 30-40 kickstarts (no electric start on mine anymore). Bike ran fine once it fired up. Happened a second time a week later, I left petcock open, fuel on floor. Same problem starting. Then ran fine.

Twice now when out on a longer ride, I've stopped and turned off engine. Pulled out maps, etc. on a short brake. Didn't turn off petcock. When I went to kickstart, wouldn't turn over and sounded flooded. Had to roll start.



Oil appears normal coloration. Carb was cleaned 1 mo ago by prior owner, this is a 2014. If float or needle leaking, wouldn't fuel be coming out bowl drain hose as well as the air filter?



elime posted a picture of this earlier in this post. The o-ring seat in the picture he posted is what deteriorated beyond all recognition and fuel started to pour out of the tube you are describing and happened to me on me this ride. Shutting off the petcock was the only thing which stopped the flow. When this happened, I was actually riding along on the trial when the TW stalled. When I stopped I could see the fuel pouring all over the ground. Before this catastrophic event happened, I had many warning signs which sound exactly what you are experiencing. I would shut the TW off out on a ride and it would not restart right away. I had no idea at the time what it could be but everything you are saying it exactly what I experienced.

When it was pointed out to me what the possible problems could be, I took the carb apart and sure enough, it was the o-ring in the picture which elime already posted.

elime's earlier posted picture and this was my problem.

 

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Discussion Starter #16
Thanks gang. I'll make sure float moves freely. I can't quite figure out where the float seat is on the service manual update. I see the float needle and pin, and looking at Lazy Man's Teikei (TK) Carb Cleaning post just assuming the float needle seats into the ...seat? So pull the pin, out slides the needle and the seat slides out next?

Last, where to get reliable replacement seat or O-ring. Dealer? Not on Procycle.
 

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Thanks gang. I'll make sure float moves freely. I can't quite figure out where the float seat is on the service manual update. I see the float needle and pin, and looking at Lazy Man's Teikei (TK) Carb Cleaning post just assuming the float needle seats into the ...seat? So pull the pin, out slides the needle and the seat slides out next?

Last, where to get reliable replacement seat or O-ring. Dealer? Not on Procycle.
Partzilla.com for TW parts.

Be careful removing the float pin. It is pressed into the float posts, and not easily removed.

Many float posts have been broken off trying to remove the pin.

Also, the float valve seat may not easily be removed.


http://tw200forum.com/forum/technical-write-ups/967-removing-carburetor-float.html




jb
 

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countless times people told me "my mechanic buddy fixed the carb" or "the yamaha shop fixed the carb" this ALWAYS means I have to go in and fix it correctly in all cases when so called yamaha shops "fixed" the carbs they were all weeping fuel from one or more places. Needle and seat are fairly temperamental IMO safer to just replace them as Rocky stated the real risk is engine oil dilution the external fuel leaks just make the snowflakes cry lol

re trailering (and I've trailered a "few" TW's) as long as the needle seat is functioning properly trailering is no different than riding your TW if the fuel in the float bowl level is high enough to close the needle valve no amount of vibration or bumps etc is going to allow the float to sink and open the valve only a defective needle seat would be at issue
 
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