Fuel Leaking out of Airbox

CarbonElite · May 1st, 2016, 02:52 PM

So, I reinstalled Ducatiman refurbed carbs a while ago and just finished up electrical and other stuff on my project. After cranking and running, fuel starting coming out of the small hole hole at the bottom of the airbox. I'm guessing I forgot to hook something up, but could have sworn did everything as I took it off when the new carbs arrived.I also don't remember the curvey hose being attached to anything(crankcase breather?) At first I thought maybe the floats were malfunctioning, but now I'm not so sure. Keep in mind, I'm a COMPLETE novice and am learning as I go. Also, disclaimer, this is by no means an indictment of Ducatimans work, I'm pretty sure I probably screwed something up(hopefully simple). Attached are a pic of the bottom of airbox where fuel was leaking out and current pic of the "almost" finished product.

ducatiman · May 1st, 2016, 03:07 PM

you bought these in january, correct?

PM coming.

CarbonElite · May 1st, 2016, 03:22 PM

Correct

Motofool · May 1st, 2016, 05:25 PM

Quote:

Originally Posted by CarbonElite

.......... I also don't remember the curvey hose being attached to anything(crankcase breather?)......

That hose should connect to the side of the airbox.

Ghostt · May 1st, 2016, 07:40 PM

@CarbonElite is that a BCB conversion?

CarbonElite · May 2nd, 2016, 05:41 AM

It is a BCB Conversion.

And Motofool, that hose doesn't line up with that outlet hole.

After talking with ducatiman, it's possible I may have a bad petcock, but continuing my research. As it is, I have to leave for DC in the AM so troubleshooting may have to wait until the weekend.

jkv45 · May 2nd, 2016, 06:12 AM

Are the screws on the floatbowl drains snugged down? They look like they are backed-out.

HoneyBadgerRy · May 2nd, 2016, 06:14 AM

That hose is the crankcase breather, and it is supposed to plug into the airbox. You can get a separate filter for that hose (it is common for people who run pods).

Your problem could be stuck floats and or a bad petcock. Did you ever get the bike running? Try shaking the carbs to get the floats free.

Sarge1992 · May 2nd, 2016, 04:06 PM

Mine did this when I first bought my 250, was a combination of a mis-adjusted float and a bad petcock. It filled my crankcase with gas, then it flowed into the airbox and down the side of the bike.

Ghostt · May 2nd, 2016, 05:06 PM

If it turns out to be the petcock, do yourself a favor and get a new one, not worth rebuilding the old one.

Alex · May 30th, 2016, 06:01 PM

Was this resolved?

FrugalNinja250 · May 30th, 2016, 06:34 PM

The float needles inside these carbs are designed to stop the flow from a full tank so if the petcock was bad it would make no difference, engine running or not. You can connect a piece of clear tubing to the nipples on the bottom of the carbs and then partially unscrew the float drain screws to open them. Then you can see how high the fuel gets in the carb bowls. Just loop the tubing upwards to a point higher than the top of the tank and don't block their ends. The fuel level in the tube should rise no higher than about the float bowl seam where it bolts to the carb body. If the fuel continues to rise past that then the float needles are likely contaminated with trash from the tank, especially if there's no quality fuel filter in the line leading to the carbs from the petcock.

May 1st, 2016, 03:07 PM	#2
ducatiman ninjette.org certified postwhore Name: Gordon Location: new york Join Date: Sep 2009 Motorcycle(s): '95 DUCATI 900SS/SP '07 DUCATI SS800 '19 HONDA CBR650R Posts: A lot. MOTM - Nov '18, Mar '17	you bought these in january, correct? PM coming. __________________________________________________ gordon@customcarbservices.com Custom Carb Service www.customcarbservices.com

May 1st, 2016, 07:40 PM	#5
Ghostt in your machine Name: Scott Location: Summer Shade, Ky. Join Date: Oct 2014 Motorcycle(s): 98 Ninja 250/F12 aka ZX-2R "SERENITY", 91 Ninja 500/A5 aka ZX-5R "Phoenix", 84 Honda GL1200A "SIREN" Posts: A lot. Blog Entries: 25 MOTM - Jun '17, May '16, Mar '15	@CarbonElite is that a BCB conversion? __________________________________________________ *violente et ignorantia* ZX-2R BLOG *Twitter and Instagram = Ghostt_Scott* *I'm not here to change your mind, just to inform.*

May 2nd, 2016, 06:14 AM	#8
HoneyBadgerRy ninjette.org certified postwhore Name: Ryan Location: Beaufort SC Join Date: Aug 2015 Motorcycle(s): 05 Ninja 250, 04 KTM 625 SMC, 01 Xc250 Posts: A lot. Blog Entries: 3	That hose is the crankcase breather, and it is supposed to plug into the airbox. You can get a separate filter for that hose (it is common for people who run pods). Your problem could be stuck floats and or a bad petcock. Did you ever get the bike running? Try shaking the carbs to get the floats free. __________________________________________________ Because Unregistered sucks at riding.

May 2nd, 2016, 05:06 PM	#10
Ghostt in your machine Name: Scott Location: Summer Shade, Ky. Join Date: Oct 2014 Motorcycle(s): 98 Ninja 250/F12 aka ZX-2R "SERENITY", 91 Ninja 500/A5 aka ZX-5R "Phoenix", 84 Honda GL1200A "SIREN" Posts: A lot. Blog Entries: 25 MOTM - Jun '17, May '16, Mar '15	If it turns out to be the petcock, do yourself a favor and get a new one, not worth rebuilding the old one. __________________________________________________ *violente et ignorantia* ZX-2R BLOG *Twitter and Instagram = Ghostt_Scott* *I'm not here to change your mind, just to inform.*

May 30th, 2016, 06:01 PM	#11
Alex ninjette.org dude Name: 1 guess :-) Location: SF Bay Area Join Date: Jun 2008 Motorcycle(s): '13 Ninja 300 (white, the fastest color!), '13 R1200RT, '14 CRF250L, '12 TT-R125LE Posts: Too much. Blog Entries: 7	Was this resolved? __________________________________________________ Montgomery Street Motorcycle Club / cal24.com / crf250l.org / ninjette.org ninjette.org Terms of Service Shopping for motorcycle parts or equipment? Come here first. The friendliest Ninja 250R/300/400 forum on the internet! (especially Unregistered)

May 1st, 2016, 03:22 PM	#3
CarbonElite ninjette.org member Name: Ken Location: Bel Air, MD Join Date: Dec 2015 Motorcycle(s): '00 Two Fiddy Posts: 41	Correct

May 2nd, 2016, 05:41 AM	#6
CarbonElite ninjette.org member Name: Ken Location: Bel Air, MD Join Date: Dec 2015 Motorcycle(s): '00 Two Fiddy Posts: 41	It is a BCB Conversion. And Motofool, that hose doesn't line up with that outlet hole. After talking with ducatiman, it's possible I may have a bad petcock, but continuing my research. As it is, I have to leave for DC in the AM so troubleshooting may have to wait until the weekend.

May 2nd, 2016, 06:12 AM	#7
jkv45 Rev Limiter Name: Jay Location: WI Join Date: Jul 2013 Motorcycle(s): '06 SV650n, '00 Derbi GPR, '64 CA77 Dream 305, '70 CL450 Scrambler, numerous dirt bikes Posts: A lot. MOTM - Jun '18, Oct '16	Are the screws on the floatbowl drains snugged down? They look like they are backed-out.

May 2nd, 2016, 04:06 PM	#9
Sarge1992 ninjette.org member Name: Ryan Location: Tampa, FL Join Date: Dec 2015 Motorcycle(s): 2014 Kawasaki Ninja 650R Posts: 67	Mine did this when I first bought my 250, was a combination of a mis-adjusted float and a bad petcock. It filled my crankcase with gas, then it flowed into the airbox and down the side of the bike.

May 30th, 2016, 06:34 PM	#12
FrugalNinja250 ninjette.org certified postwhore Name: Frugal Location: Dallas/Fort Worth (DFW) Join Date: Mar 2010 Motorcycle(s): Several Posts: A lot.	The float needles inside these carbs are designed to stop the flow from a full tank so if the petcock was bad it would make no difference, engine running or not. You can connect a piece of clear tubing to the nipples on the bottom of the carbs and then partially unscrew the float drain screws to open them. Then you can see how high the fuel gets in the carb bowls. Just loop the tubing upwards to a point higher than the top of the tank and don't block their ends. The fuel level in the tube should rise no higher than about the float bowl seam where it bolts to the carb body. If the fuel continues to rise past that then the float needles are likely contaminated with trash from the tank, especially if there's no quality fuel filter in the line leading to the carbs from the petcock.

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