318 2bbl won't idle without choke

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The small check ball goes under the venturi assy.
The large check ball goes under the accelerator pump.
The float is adjusted with the carb upside down. This limits the amount of pressure on the needle and seat. Only the weight of the float assy is necessary.
 
TT5.9mag said:
Watch the video for the bbd carb float setting at the link I provided. Mike is a very knowledgeable carb guy and he’s doing it a different way.
“Lightly press the float tang down to seat the needle and measure the top of the float”. Now I’m not saying one way is right or wrong. I’m saying it’s different.
Click to expand...

Here's the video link:
 
pt70 said:
The small check ball goes under the venturi assy.
The large check ball goes under the accelerator pump.
The float is adjusted with the carb upside down. This limits the amount of pressure on the needle and seat. Only the weight of the float assy is necessary.
Click to expand...
I know the FSM and mikes video differed that’s why I suggested another method. Maybe something will change.
Phreakish said:
Here's the video link:
Click to expand...

Thanks for posting the video.
 
This to me sounds like one of only two things;
1. Float level
2.needle/seat
Maybe it’s not the original carb and it’s one of those bbd carbs that has a different float measurement.
 
New needle and seat just put in; didn't help but I think I've noticed something. It looks like it's related to the accelerator pump. When I insert the rod for the pump lever, gas starts leaking out of the throttle shaft. Maybe I have the rod set wrong or I'm using the wrong air horn gasket? The kit came with three and I'm using the one most similar to what I removed, as opposed to the one in Mike's video that seems to cover the accelerator pump area.

Update: Ok, I think the fuel leaking around the throttle shaft is only happening when I actuate the throttle or the pump lever with the car off. The fuel squirts into the bore and since the throttle plates are closed, I guess it has nowhere to go and just leaks out the throttle shaft. I can't get it to flood with the air horn off turning the key (with the coil disconnected) to build pressure, so maybe the needle and seat did help. However, it still runs VERY badly, won't rev well at all, and fuel still drips from the venturis.
 
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Remove the floats. Shake them to see if they have gas in them if they're brass. If they are cracked, you will hear gas. If they're the black plastic, dry them off good and then squeeze them gently. If gas appears on the float surface when you squeeze them, they are compromised with fuel and are too heavy causing the needle to stay open and flood the carburetor. Either way, it will need a new float assembly.
 
RustyRatRod said:
Remove the floats. Shake them to see if they have gas in them if they're brass. If they are cracked, you will hear gas. If they're the black plastic, dry them off good and then squeeze them gently. If gas appears on the float surface when you squeeze them, they are compromised with fuel and are too heavy causing the needle to stay open and flood the carburetor. Either way, it will need a new float assembly.
Click to expand...

Tried that this morning. Floats are good, they're brass and had no sloshing or leaks with the dunk-in-water and rotate test.
 
Have you tried more advance?
Just pull on the V-can, while the engine is running, until it smooths out, forget about the timing light; just pull !

And wire that stinking choke open !
 
It’s dripping from the boosters. Either the floats are set too high or the needle isn’t shutting off the flow.
 
Try this....set the damn floats at 3/8” and see how it idles.
 
Try this, put a vacuum guage on it.....pinch the fuel hose with some vice grips to lower the fuel pressure. 6psi sounds high for a Carter. Did the kit come with more than one size 'power piston' seals? I had a dirty Nikki carb..had to set curb idle to 1200 for it to idle then I sprayed a half a can of carb cleaner in and around the throat to clean it, it finally coughed and then cleared up big time and wound up to 2000 so I lowered it back down to 750 and it idled great. I think it was some air bleeds gummed up with **** ethanol blend jello as I concentrated the spray on the little brass orifices around the throat. Im now starting it once a week to keep it clear.
 
I rebuild the same carb. Pictures tell more than a thousand words. Please attach some good, detailed and clear pictures from all sides of your carburetor. If you have pictures from the rebuild post them too. Maybe there is something obvious visible.

Cheers,
Wolfgang
 
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FYI
that carb can be idled all day with the top off, so long as the horseshoe clip is holding the float in place.

I have not had many factory SMB pumps, maybe a dozen, and only the 340 pumps occasionally make 6 psi. The others run 3.5 to 4.5

Like others have said, if the boosters are dribbling,the liquid level in the bowl is way to high; or the choke blade is bringing the manifold vacuum to the top.

FYI:
One other thing I discovered, is that the boosters don't care which way the air moves thru them, to flow. I had an engine once with a jumped timing chain, that only barely idled with the throttles wide open, and the ignition over-advanced. Air was actually being pumped backwards thru the carb, and a cloud of fuel was hovering above the airhorn. I was very young then, but it didn't take long to figure out something was seriously wrong!!
A similar thing can happen, at or close to fast-idle, if the intake valves, for whatever reason,are not fully closing. But in this case,if you open the throttle too far, she will start to send compressed mixture on fire, back into the intake. Which can/usually does pop up thru the carb. FYI
 
I agree that this is definitely difficult to troubleshoot via text. I took the carb apart again and put it back together with lots of photos, so let's rebuild a carb together FABO...
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Continued. As you can see, my float measurement seems to read a bit low if anything. I'm gently pressing it against the needle/seat in these photos.

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That looks good and well documented! Will take more time later, but what I can see now, the rod on the plunger arm should be in the inner hole and in the middle hole at the throttle lever. Had it first like you but changed the position after reading the BBD manual below. Can’t see it on the pictures, but is there a check ball (larger one) under the plunger? Are all the needles and passages on the Venturi lid and cluster free? Did you blow air through all passages of the carb, carb lid and made sure those passages are free?
Here is a good manual covering several BBD models:
http://u225.torque.net/cars/SL6/docs/BBD_Manuals.pdf

Wolfgang
 
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Your second video it seems to be running better. And less fuel dripping from the boosters. Did you try lowering the floats to 3/8” or so?
 
When I first got my Aussie Charger many years ago it idled like **** and would take a while to start when hot. I rebuilt the carb (2 barrel carter ) two or three times with no change. I was given a second hand carter and I rebuilt that and all my issues were solved.I could not see any issues with the first carb but suspect it had a crack in it somewhere that would open up more when hot, or a warp somewhere.
 
Tylinol said:
Continued. As you can see, my float measurement seems to read a bit low if anything. I'm gently pressing it against the needle/seat in these photos.
Click to expand...

If you have to push down on the float to read the 1/4, then the float is set TOO HIGH,
not
" bit low"
And with float level, a bit is a lot.
 
Do idle screws change anything?
I still thing something is plugged. I set them at 1-1/2 turns out. Then go from there.
 
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