Bike won't start, keeps flooding



11 replies to this topic
  • AKmotorider

Posted July 13, 2013 - 07:34 PM

#1

[color=#000000][font=Arial, Verdana][size=3]Bike started fine a couple days ago, now when I try to start it it immediately floods out. After 3 kicks its dripping gas. Compression is no the problem, I maintain that stuff meticulously. I suck with carbs though. Whats the issue? Tried the choke and the hot start and nothing at all multiple times, nothing is happening. Just pours out gas.[/size][/font][/color]

  • KX100BRAAP

Posted July 13, 2013 - 08:25 PM

#2

Clean the carb. I think your floats are getting stuck

  • 87XR250R

Posted July 14, 2013 - 01:42 AM

#3

Float is stuck, should not drip gas unless it is upside down on the side of the trail. You should not have to twist the throttle on a 4 stroke with an FCR carb to start it. The pump in the carb will flood the engine. If the float is not leaking try holding the throttle wide open when kicking to clear it out and get it running.

  • AKmotorider

Posted July 15, 2013 - 10:37 PM

#4

[color=#000000][font=Verdana, Arial, Tahoma, Calibri, Geneva, sans-serif][size=3][background=rgb(251, 251, 251)]Alright, I took the carb all apart, blasted everything with carb cleaner, set the float height (sure enough, it was off), put it all back together, and it still won't start. I also took a good look at the float, float needle, and the needle seat and everything looks fine. I fact, it looks perfect. No signs of wear. I made sure it is getting air, also checked the spark, and took a good look at the fuel and it looks clean. Just to make sure, I'm going to drain the AVGAS thats in it and go buy some genuine racing fuel tomorrow and see if that helps at all, but I doubt it. What other suggestions do you guys have? I'm at a complete loss. The carb is now spotless, it has compression and spark...I just don't know.[/background][/size][/font][/color]

  • Do I Care?

Posted July 15, 2013 - 11:00 PM

#5

[color=#000000][font=Verdana, Arial, Tahoma, Calibri, Geneva, sans-serif][size=3][background=rgb(251, 251, 251)]Alright, I took the carb all apart, blasted everything with carb cleaner, set the float height (sure enough, it was off), put it all back together, and it still won't start. I also took a good look at the float, float needle, and the needle seat and everything looks fine. I fact, it looks perfect. No signs of wear. I made sure it is getting air, also checked the spark, and took a good look at the fuel and it looks clean. Just to make sure, I'm going to drain the AVGAS thats in it and go buy some genuine racing fuel tomorrow and see if that helps at all, but I doubt it. What other suggestions do you guys have? I'm at a complete loss. The carb is now spotless, it has compression and spark...I just don't know.[/background][/size][/font][/color]

Did adjusting the float height fix the ''gas dripping'' issue?
Did you check the float valve (needle seat) O-ring is not perished? These perish over time.

  • Do I Care?

Posted July 15, 2013 - 11:04 PM

#6

Also if you took the fuel metering screw out, make sure that it is still in there. It goes- fuel metering screw, spring, washer, O-ring. This O-ring may be perished.

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  • AKmotorider

Posted July 16, 2013 - 12:41 AM

#7

Also if you took the fuel metering screw out, make sure that it is still in there. It goes- fuel metering screw, spring, washer, O-ring. This O-ring may be perished.

Yup, set that. Its all in order.

  • grayracer513

Posted July 16, 2013 - 06:50 AM

#8

Did you check the float valve (needle seat) O-ring is not perished? These perish over time.


'03 or later has no O-ring on the needle seat; the seat is not removable. '02 and earlier are, and the seal does fail after a while. There's also a serviceable screen on the removable seats.

  • Do I Care?

Posted July 16, 2013 - 05:49 PM

#9

'03 or later has no O-ring on the needle seat; the seat is not removable. '02 and earlier are, and the seal does fail after a while. There's also a serviceable screen on the removable seats.

Ahr, yes thanks for the info Greyracer (Grayracer).

That's a better design then the Gen 2 or 1 then. :thumbsup:

  • grayracer513

Posted July 17, 2013 - 06:07 AM

#10

The fixed seat? It is and it isn't. The needle seat wears over time, but can't be replaced. In practice, however, the seats do seem to hold up for the practical life of the rest of the carb body. :excuseme:

  • Do I Care?

Posted July 17, 2013 - 06:33 AM

#11

The fixed seat? It is and it isn't. The needle seat wears over time, but can't be replaced. In practice, however, the seats do seem to hold up for the practical life of the rest of the carb body. :excuseme:

Yeah I was thinking that and why I said it was a good thing. At least you don't have to replace the O-ring though. On the other hand, the cable for the hotstart is a bad design IMO, as water would run down the cable and seize it over time.

  • NitrousR1

Posted July 17, 2013 - 02:51 PM

#12

After your carb cleaning does it still leak fuel out the overflow? If so you have a bad seal between the float needle and the seat or the float height is still off and needs rechecked. I always test them on the bench with a mityvac vacuum brake bleeder pump.





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