Author Topic: Carb blowing fuel out air horn!!!!  (Read 8066 times)

Offline Chryco Psycho

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Re: Carb blowing fuel out air horn!!!!
« Reply #15 on: April 24, 2016 - 12:28:59 AM »
I have seen the air past the squirter nozzle pull fuel into the air stream  Holley makes enclosed squirter that will prevent this 
I have added a picture , the one to the right is boxed in & will not allow fuel to be lulled into the air stream

Challenger - You`ll wish You Hadn`t




Offline 734406pk

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Re: Carb blowing fuel out air horn!!!!
« Reply #16 on: April 24, 2016 - 09:26:13 AM »
I have seen the air past the squirter nozzle pull fuel into the air stream  Holley makes enclosed squirter that will prevent this 
I have added a picture , the one to the right is boxed in & will not allow fuel to be lulled into the air stream

That makes sense. Is the fuel being drawn in through the (wrong) squirter nozzle or blowing out the bowl vent?
« Last Edit: April 27, 2016 - 03:19:25 AM by 734406pk »
1973 Challenger 440 6 pack auto 3.91 rear
2012 Dodge Ram 3500 dually 6.7 Cummins Fleece EFI Live
1973 Challenger 318 2bbl auto 2.73 rear 22.5 mpg RIP
1970 Challenger TA 340 4bbl auto-Sold and sad
1999 Dodge Ram 3500 dually 5.9 Cummins Fleece tuned VGT-sold
1995 Kawasaki ZX1100E & still alive

Offline BS CUDA

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Re: Carb blowing fuel out air horn!!!!
« Reply #17 on: April 24, 2016 - 01:11:39 PM »
It will be in the 20C range again next weekend - I will take her out flog it and see if it is cured. Don't think it would hurt anything to change to those nozzles but 1 thing at a time to fin the "actual" solution.

Don't think that is the problem though as mine pours fuel out the vents / air horns / carb tubes or whatever they are called. Just may find this carb on Kijiji soon lol.

Offline Chryco Psycho

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Re: Carb blowing fuel out air horn!!!!
« Reply #18 on: April 24, 2016 - 02:29:48 PM »
have you contacted Holleys Tech line  :dunno:

Challenger - You`ll wish You Hadn`t

Offline 734406pk

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Re: Carb blowing fuel out air horn!!!!
« Reply #19 on: April 24, 2016 - 03:19:42 PM »
Take a cell phone video of the event if possible. It can be very helpful and save time.
1973 Challenger 440 6 pack auto 3.91 rear
2012 Dodge Ram 3500 dually 6.7 Cummins Fleece EFI Live
1973 Challenger 318 2bbl auto 2.73 rear 22.5 mpg RIP
1970 Challenger TA 340 4bbl auto-Sold and sad
1999 Dodge Ram 3500 dually 5.9 Cummins Fleece tuned VGT-sold
1995 Kawasaki ZX1100E & still alive

Offline BS CUDA

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Re: Carb blowing fuel out air horn!!!!
« Reply #20 on: April 24, 2016 - 06:00:44 PM »
have you contacted Holleys Tech line  :dunno:

Oddly enough no - that would have been too logical lol. These carbs seem so simple and parts cheap and readily available I figured sooner or later the right part would get replaced.

I may just try bending the needle tang on the float a bit if it happens again - couldn't hurt. 

Offline BS CUDA

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Re: Carb blowing fuel out air horn!!!!
« Reply #21 on: April 24, 2016 - 06:02:24 PM »
Take a cell phone video of the event if possible. It can be very helpful and save time.

That is probably a great idea - unsure why I haven't already done this.

Offline Denison636

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Re: Carb blowing fuel out air horn!!!!
« Reply #22 on: April 24, 2016 - 09:55:11 PM »
Just curious if you have ever checked to see if you header/ exhaust is pulling vacuum. I know sometimes this happens when you have a wrong can for your motor combo.
Its just a little 340 with a miss

Offline 734406pk

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Re: Carb blowing fuel out air horn!!!!
« Reply #23 on: April 24, 2016 - 11:33:23 PM »
It's a long shot but could you possibly be missing this part?
1973 Challenger 440 6 pack auto 3.91 rear
2012 Dodge Ram 3500 dually 6.7 Cummins Fleece EFI Live
1973 Challenger 318 2bbl auto 2.73 rear 22.5 mpg RIP
1970 Challenger TA 340 4bbl auto-Sold and sad
1999 Dodge Ram 3500 dually 5.9 Cummins Fleece tuned VGT-sold
1995 Kawasaki ZX1100E & still alive

Offline BS CUDA

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Re: Carb blowing fuel out air horn!!!!
« Reply #24 on: April 25, 2016 - 09:33:11 PM »
Just curious if you have ever checked to see if you header/ exhaust is pulling vacuum. I know sometimes this happens when you have a wrong can for your motor combo.

And this can be checked how?

Offline BS CUDA

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Re: Carb blowing fuel out air horn!!!!
« Reply #25 on: April 25, 2016 - 09:35:27 PM »
It's a long shot but could you possibly be missing this part?

Don't know how you got that out of there? Mine is in there but is roughly 1/2" down the hole and a magnet won't pick it out. It is somewhat free as I used a pick to reach in and "jiggle" it.

Offline Denison636

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Re: Carb blowing fuel out air horn!!!!
« Reply #26 on: April 25, 2016 - 10:43:43 PM »
Usually see this if vacuum drops as you go into the rpms. It can be a very little amount like 1". Plugs will show good but your exhaust temp will be high also to. The motor should make vacuum as you go into the r's and never drop. If it drops then you can have what you have going on. A cam with big duration and over lap usually do this and you run a evacuation system from your valve cover to headers that will pull vacuum for you and the intake will then pull it and your carb stops doing what your talking about.
This is just what I have seen in the past but everyone has there own fix.
So first check vacuum while driving and see when that happens if it drops. Then check valve adjustment with a timing light to each cly. Then last is exhaust temp.
Its just a little 340 with a miss

Offline 734406pk

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Re: Carb blowing fuel out air horn!!!!
« Reply #27 on: April 26, 2016 - 02:32:16 AM »
Don't know how you got that out of there? Mine is in there but is roughly 1/2" down the hole and a magnet won't pick it out. It is somewhat free as I used a pick to reach in and "jiggle" it.

That's ok  no need to remove the check valve, just need to verify that it is in place. It is made of brass and  is non-magnetic btw.
1973 Challenger 440 6 pack auto 3.91 rear
2012 Dodge Ram 3500 dually 6.7 Cummins Fleece EFI Live
1973 Challenger 318 2bbl auto 2.73 rear 22.5 mpg RIP
1970 Challenger TA 340 4bbl auto-Sold and sad
1999 Dodge Ram 3500 dually 5.9 Cummins Fleece tuned VGT-sold
1995 Kawasaki ZX1100E & still alive

Offline 734406pk

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Re: Carb blowing fuel out air horn!!!!
« Reply #28 on: April 27, 2016 - 09:58:31 AM »
This issue may be the vent tube itself. The slash cut 45 deg angle on the vent tube should be facing outward against the direction of air flow (to prevent a venturi effect).  You can fabricate longer vent tubes with 5/16" steel brake line tubing  cut at 45 deg to increase the distance from the intake airstream, just leave at least 3/8" space from the air filter top cover. Another option would be these custom machined brass 90 deg bowl vents available in various lengths from BLP.COM:
http://blp.com/pdf/2010c/section1/2010Section1-8.pdf
 
« Last Edit: April 27, 2016 - 10:00:39 AM by 734406pk »
1973 Challenger 440 6 pack auto 3.91 rear
2012 Dodge Ram 3500 dually 6.7 Cummins Fleece EFI Live
1973 Challenger 318 2bbl auto 2.73 rear 22.5 mpg RIP
1970 Challenger TA 340 4bbl auto-Sold and sad
1999 Dodge Ram 3500 dually 5.9 Cummins Fleece tuned VGT-sold
1995 Kawasaki ZX1100E & still alive

Offline BS CUDA

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Re: Carb blowing fuel out air horn!!!!
« Reply #29 on: May 07, 2016 - 10:42:13 PM »
Seems to be heat related - ran good yesterday in low 20's (Celsius). Today started spewing close to home in the 28 Celsius range - fuel pump was also very loud (Holley billet electric). Between this, the oil leak the engine shop can't seem to fix, and my street bike with intermittent start issues - almost time to sell all the toys and buy a good pair of shoes and go for a walk.