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Old 01-13-2021, 10:49 AM   #1
Droff
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Carb leak at choke location

I've got a manual choke Edelbrock carb that is leaking at one of the ports on that side. I don't have anything connected to the choke so it isn't being used.
I have little experience with carbs so I've only tightened both of the bolts on the side, don't want to go any tighter.

Would a rebuild kit address this issue or is there something else I need to look into?
Thanks.
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Old 01-13-2021, 11:43 AM   #2
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Re: Carb leak at choke location

What kind of leak? Vacuum or gas.
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Old 01-13-2021, 11:44 AM   #3
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Re: Carb leak at choke location

Gas
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Old 01-13-2021, 12:25 PM   #4
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Re: Carb leak at choke location

You got gas there, it’s flooding.
Multiple things to check.
Could be trash in needle/seat, stuck float, sunk float or the most common flooding issue with edelbrocks carbs which is too much fuel pressure.
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Old 01-13-2021, 01:00 PM   #5
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Re: Carb leak at choke location

Quote:
Originally Posted by geezer#99 View Post
you got gas there, itís flooding.
Multiple things to check.
Could be trash in needle/seat, stuck float, sunk float or the most common flooding issue with edelbrocks carbs which is too much fuel pressure.
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Old 01-13-2021, 02:14 PM   #6
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Re: Carb leak at choke location

Quote:
Originally Posted by geezer#99 View Post
You got gas there, itís flooding.
Multiple things to check.
Could be trash in needle/seat, stuck float, sunk float or the most common flooding issue with edelbrocks carbs which is too much fuel pressure.
Ok. There's a good chance it could be trash, I think I could use getting the tank cleaned.
So for the carb, as I said, not much experience. Just best to start with a rebuild kit or start poking around at each possible issue?
As far as fuel pressure, I've got just a regular fuel pump.
Thanks.
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Old 01-13-2021, 02:30 PM   #7
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Thumbs up Re: Carb leak at choke location

As far as I know they don't make any kits that will fix the side bores on these. I had one a while back that the gas pedal linkage was sloppy. I called Edelbrock to see what to order. They said no kits available for these issue.

I found a local guy after buying a new carb. and he fixed it for me.
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Old 01-13-2021, 03:15 PM   #8
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Re: Carb leak at choke location

Quote:
Originally Posted by Droff View Post
Ok. There's a good chance it could be trash, I think I could use getting the tank cleaned.
So for the carb, as I said, not much experience. Just best to start with a rebuild kit or start poking around at each possible issue?
As far as fuel pressure, I've got just a regular fuel pump.
Thanks.
Start it up and look in the carb.
You shouldnít see any raw fuel while itís idling.
If you do let us know.
Do you have any rubber hose on the fuel line from the pump to the carb?
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Old 01-13-2021, 03:48 PM   #9
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Re: Carb leak at choke location

Quote:
Originally Posted by geezer#99 View Post
Start it up and look in the carb.
You shouldnít see any raw fuel while itís idling.
If you do let us know.
Do you have any rubber hose on the fuel line from the pump to the carb?
I'll give that a check.
On the rubber hose, yes I do. I've got a filter inline sitting along the frame and it's rubber from the filter to the pump. From the pump up it's about 50/50 hardline and rubber to the carb. I've got a second filter inline just prior to the carb.
The setup is how it was when I bought the truck, haven't done anything to change it.
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Old 01-13-2021, 05:04 PM   #10
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Re: Carb leak at choke location

I’ve used a pair of pliers to gently squeeze rubber fuel line to reduce the flow. Acts like a fuel regulator. Less flow will likely stop any flooding you see inside. That will show fuel pressure is too high.
Sometimes when you release the hose the extra fuel can also help flush out any crap in the needle/seat.
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Old 01-13-2021, 06:01 PM   #11
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Re: Carb leak at choke location

hi,with regards to your carb problem.if it's leaking because it's flooding,as was already said you may have some crap in the needle and seat,not letting the flow of fuel stop or slow down when the float raises.i do a bunch of Quadrajets here and see one often that is flooding because the tank is full of crap.sometimes i am able to hit on the front of the carb by the fuel line with a rubber hammer,just easy and once in a while,the crap will dislodge and problem is solved,more often than not,i have to pull the top off and clean out the crap.sometimes you can get the air horn off without killing the gasket,sometimes,no such luck.if you have the carb apart,if it is stopped up with crap and it's dirt and rust and so on,the tank is dirty,but you might see bits of rubber,indicating a hose is failing.good luck.
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Old 01-13-2021, 06:19 PM   #12
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Re: Carb leak at choke location

I've got fuel sitting on both sides of the carb when running, see arrows.
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Old 01-13-2021, 06:32 PM   #13
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Re: Carb leak at choke location

Try the hose trick.
Might be need for a regulator.
Or float adjustment.
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Old 01-13-2021, 07:21 PM   #14
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Re: Carb leak at choke location

Tried the hose trick, squeezed it for around 30-40 seconds, no difference in idle or level of fuel in the carb. I pretty much had it clamped, not just restricted a bit.
Need to go longer?
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Old 01-13-2021, 07:41 PM   #15
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Re: Carb leak at choke location

Don’t hurt to try longer.
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Old 01-14-2021, 02:16 PM   #16
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Re: Carb leak at choke location

I'll give that another shot but I figure I'll just cut to the chase and pull the tank to get it cleaned and coated as well as get a rebuild kit for the carb. I'm pretty sure I have a lot of crud in the tank, the filters get clogged fairly easy.
No point in leaving the carb out of the equation.
Thanks.
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Old Yesterday, 09:43 AM   #17
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Re: Carb leak at choke location

As you may have read on this site and elsewhere, Edelbrock carbs don't like more than 5-6psi of fuel. I installed a regulator and gauge, which really helped. The VDO gauge was made in the USA.

I rebuilt a 1405 before switching to an AVS2 1905. They are easy to rebuild in my opinion.
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