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Center carb pouring gas out of vent tube

440beep

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So my center carb is pouring gas out of the vent tube while the car struggles to start. It attempts to start, but then the fuel comes pouring out of the primary vent tube and nothing happens. I've put in a new needle and seat, and nothing. Below is some history on the situation.

Last Saturday while the driving the car, it sporadically started acting funny. The RPMs started to stumble, they would drop below a 1000 RPM then the car would sputter and die. I could restart it, drive a lil further, and same thing, sputter and die. Did this off and on until finally the car would not restart and fuel was pouring out of the center vent tube while trying to restart. However, earlier in the day I did adjust the float levels (center was way low) and idle mixture screws and the car ran great!! While trying to diagnose the issue, I've replaced the orange ECU and ballast resistor with new ones. Now the car will partially start, but as its trying to start fuel is pouring out of the primary vent tube but won't stay running. If the float is stuck, is there anyway to get it loose without taking the fuel bowl off? Any other ideas of what the heck is wrong with this car please?
 
Only two things,needle/seat or gas in float.
 
On Holley A shaped bowls you can remove the needle and seat from the carb without having to remove the bowl, can't you?!
 
Yes, loosen the tightening screw, unscrew the adjustmnet nut and out it comes. I installed a new one yesterday with no success, fuel comes out the vent tube like Old Faithful while trying to start. Looking now for the primary carb fuel float part# so I can get a new one.

On Holley A shaped bowls you can remove the needle and seat from the carb without having to remove the bowl, can't you?!
 
I would pull the bowl and check the float to make sure it isnt full of gas and blow air thru where the fuel comes into the bowl. I found a metal shaving in my rear bowl and it was causing fuel to keep flowing after I shut the engine off. Its just 4 bolts and you dont want that getting deeper into the carb.
 
So here's a noob question, can I get the fuel bowl off without taking the carb off the motor? I'm guessing not by the looks of the fuel bowl screws and how long they are. Or can I just loosen the fuel bowl screws and lift the entire assembly off the throttle body? Its my first time working on a carb.

What causes a hole or crack in the fuel float? I can't understand how all of a sudden the car went from fantastic to crap in less than 6 hours.
 
i have never tried on that setup.try to get all the bowl screws loose and see what happens.worst thing that can happen is you have to take the carb the rest of the way off.you would have to do that anyhow.
 
As stated above it is likely that it is just some debris blocking the needle from seating properly in the seat ... had this happen to me also ... couple of taps with a screwdriver dislodged the debris ... but I still took it apart to clean it properly.

Are you running a stock mechanical fuel pump or an aftermarket electric?
 
I just thought of something, if I take the bowl off with the carb on the car, won't all the fuel spill out that's in there? Or even start spilling out as I loosen the attaching screws? Probably best that I take the entire carb off since I want to look at the PV, check the gaskets, and maybe install the 50cc accelerator pump.

i have never tried on that setup.try to get all the bowl screws loose and see what happens.worst thing that can happen is you have to take the carb the rest of the way off.you would have to do that anyhow.

- - - Updated - - -

Stock fuel pump.

Are you running a stock mechanical fuel pump or an aftermarket electric?
 
Yes if you take the bowl off you will spill fuel, I just place a few paper towels under there and get to work. Taking it off the engine isnt required, but it will make things a little easier.
 
Thanks guys for all the information/help. Picking up a new fuel float after work.

But first I have to fix another, bigger problem I created last night. Broke off a valve cover stud clean in the head, so now I have to f**k with it and try and "easy out" it. Me and anything mechanical don't get along. :(
 
I was Mr Murphy's case study. :( And the pisser is there are huge car shows next weekend that I need to go to, so the pressue is on. Just need to relax, work slowly, and double think everything before doing something.

Sounds like Mr. Murphy has your number! Good luck
 
When I bought my RR last nov, I had all kinds of carb problems. Ive taken it off and back on 20+ times, talk about frustrating, im good to go now, but I feel your pain. I have a holley with non adjustable floats too, im getting used to it but I like the old school ones better.
 
I've never worked on a carb before and have no one to stand over my shoulder for support/help; so just a little nervous. But it seem easy enough. perhaps I will watch a few more Youtube videos on the process.
 
There is really nothing to it. I like to have a super clean work area when im doing carb work. Stay organized and if you have a smart phone or digital camera take some reference pics as your taking it apart so you can make sure your putting it back together right.
 
BTW, recommend you save your money on the 50cc pump. Not necessary if the pump linkage is adjusted correctly; that is, any movement in the throttle results in fuel squirting from the nozzle. When you get the carb off, remove the bowl and the needle/seat. Blow high pressure air through the fuel inlet area. Replace the needle (spit on the 'o' ring to lube it) and invert the bowl. Adjust the needle/seat so that a 1/4" drill bit just fits between the bottom inside of the bowl and the float. Use new gaskets between the metering block, carb, bowl screws and bowl. Check the new gaskets against the old and use a new base gasket. Readjust float level after you get the motor running so fuel is just at the level of the site plug hole. Good luck.
 
So how the heck are you supposed to get the mounting bolt out on the fuel line side when the damn fuel line is in the way that leads to the back secondary?! The mounting bolt next to the back secondary is hitting the hard fuel line. WTF?!
 
take the line off?sometimes it is just easyer to disassemble a bunch of stuff to do something simple.
 
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