still flooding

ALLAN

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1970 318 Polara auto, Carter BBD.
Its been a problem for a while, I've tried cleaning carb and tank, fresh needles, check float height etc but the carb still floods after the engine has been run, i.e start the engine, let it run /drive for a while till warm shut down, the carb floods to the point where fuel is present around the gasket seams.
My thoughts are float/needle sticking open, float holed, choke. Either way if I try to restart the car its flooded. It has also cut out on decel.
car starts fine when cold or allowed to stand.
Are plastic floats available for Carter BBDs?
 
I had the same trouble with mine. I put a reman on it and runs fine now. I still have the flooder. Haven’t dug into it yet, but I checked needle, seat, floats and float levels and never found anything wrong. Mine would geyser fuel out of the bowl vent.

The problem I had was just like yours. Cold, it was fine. Once the car warmed up, it would flood. I could drive it, but if I stopped somewhere it was hell getting it cranked and running again. I, too, would like to know the solution to this.

Fuel pump pressure? I’ve read that some of the new fuel pumps have poor quality control and pressure can be excessive.
 
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I wonder if Dana(the member with the carb shop would have any ideas.My 65 Sport Fury 318 2 bbl. does the same thing.
 
Chatting with a local guy with an MG, his does this but clears after the car has been used for a few days, he thinks the float sticks due to residue..
 
1970 318 Polara auto, Carter BBD.
Its been a problem for a while, I've tried cleaning carb and tank, fresh needles, check float height etc but the carb still floods after the engine has been run, i.e start the engine, let it run /drive for a while till warm shut down, the carb floods to the point where fuel is present around the gasket seams.
My thoughts are float/needle sticking open, float holed, choke. Either way if I try to restart the car its flooded. It has also cut out on decel.
car starts fine when cold or allowed to stand.
Are plastic floats available for Carter BBDs?

Check you heat riser to be sure it is not stuck shut as this will overheat the carb and cause fuel to boil and flood the engine. Sometimes a float that has fuel leaking inside of it will cause the needle valve to not close properly. At this point I would suggest removing the float and shaking it to see if you can feel liquid sloshing about inside the float. Floats that have a bunch of gunk on the outside are also going to be heavy and not close properly. Also check the gasket on the brass seat for the needle valve as those sometimes leak as well.

Dave
 
Fuel pump pressure? I’ve read that some of the new fuel pumps have poor quality control and pressure can be excessive.
Agree you may want to check fuel pressure. Recently had a mechanical pump that put out erratic pressure, sometimes way too high. You have to tee in a pressure gauge to see what's happening. I put in some long hoses and watched pressure when driving. Changed to a different pump & very steady at 5-6 PSI. Might want to eliminate this possibility before diving into the carb.
 
Check you heat riser to be sure it is not stuck shut as this will overheat the carb and cause fuel to boil and flood the engine. Sometimes a float that has fuel leaking inside of it will cause the needle valve to not close properly. At this point I would suggest removing the float and shaking it to see if you can feel liquid sloshing about inside the float. Floats that have a bunch of gunk on the outside are also going to be heavy and not close properly. Also check the gasket on the brass seat for the needle valve as those sometimes leak as well.

Dave
Ah yes! forgot about this. Its not seized but not free, may be the problem, is it possible to tell its position in situ? I was tempted to remove it when I found it seized but it freed off,only to start sticking again.
 
Agree you may want to check fuel pressure. Recently had a mechanical pump that put out erratic pressure, sometimes way too high. You have to tee in a pressure gauge to see what's happening. I put in some long hoses and watched pressure when driving. Changed to a different pump & very steady at 5-6 PSI. Might want to eliminate this possibility before diving into the carb.
Hmm.. I fitted a new pump last year when the original one started draining down.
 
Ah yes! forgot about this. Its not seized but not free, may be the problem, is it possible to tell its position in situ? I was tempted to remove it when I found it seized but it freed off,only to start sticking again.

The heat riser valve has a spring attached. As the engine warms up the spring looses tension and the valve opens, reverse is also true, a cold spring gains tension and closes the valve. If you have the type of heat riser with the weight that is a rectangular block, the valve is open when the block is fully down. There were several different types of heat risers, the important thing is that when cold, the valve should close itself freely and you should feel spring tension as you try to open it.

Dave
 
Hmm.. I fitted a new pump last year when the original one started draining down.
The faulty pump I mentioned was new. Quality control on many new parts is suspect, personally I've had any number of failures including multiple master cylinders (scary) & I just do this stuff for a hobby. Mechanics can tell you horror stories.
 
The faulty pump I mentioned was new. Quality control on many new parts is suspect, personally I've had any number of failures including multiple master cylinders (scary) & I just do this stuff for a hobby. Mechanics can tell you horror stories.

There have been a lot of issues with the ChICom pumps sold at Autobone and Carcrap. Good reason to source a Carter pump as they usually are good quality.

Dave
 
There have been a lot of issues with the ChICom pumps sold at Autobone and Carcrap. Good reason to source a Carter pump as they usually are good quality.

Dave
The pump was a Carter! No mfg country was specified on the item if I recall correctly.
 
well the heat riser was stuck closed, with broken springs. now locked open, not like its going to be used in cold conditions. Also found the float has failed so not surprising it flooded. Just waiting for mr Fed Ex to decide if he's going to deliver. :thumbsup: oh and this cursed plague to go away so we can go out and play. Stay Safe .
 
Once fixed, BE SRUE to change the motor oil! Fuel dilution (past the piston rings) dilutes the motor oil. Not good. Plus a new oil filter.

The local dealer used to sell a good number of Belvederes to older ladies. They used their car regularly, but for a few miles at a time. Other than the heat riser sticking, as the cars never got fully warmed-up, the heat crossover in the intake manifold would plug up with carbon. As the automatic choke thermostat was operated by heat in that passage, the thermostat would not let the choke usually come off of fast idle, even when the engine was warm. Had to remove the intake manifold and chisel it out (or whatever) so the choke would work as designed, again. Make sure you might not be having (or getting ready to have) that problem, too.

Keep us posted,
CBODY67
 
SOOO.. after doing my back in changing the points etc I decided to attack the carb. slight weeps at joints and flooding, after cleaning I spotted the obvious. the top of the carb is bowed at a couple of places. Quite badly across the front ( float end). What replacement carb should I look for, there are a couple of dubious looking items on the web. I'm happy with the performance so just need a straight swap. BBD pt#4895S (2249/2027)
did think about skimming it but its weeping from the spindle.
 
Had nothing to lose so I flattened the air horn down with the old wet and dry paper on thick glass trick. Now seals a treat,car starts on the button and runs beautifully, got a Paddington hard stare from the Boss when I social distanced from the lights I feel the main problem had been the stuck heat riser causing overheating around the carb,we'll see. Stay safe and don't inject disinfectant
 
Having a flooding issue aswell, when hot. Motor will not fire unless i WOT and keep it down till the motor fires initially, indicative of a flooding engine maybe associated with fuely smells?
Just thinking outloud, hopefully it will be food for thought for some folks.
Planning on lightly tapping on the air horn with a screw driver and to see if any crud that might have lodged it's self in the needle & seats comes loose, if not i'll inspect the needles & seats with the airhorn off and manually clean the nooks and crannies, and perhaps lower the fuel pressure to acomodate the fuel volatility of today's crap gas, fuel pressure right now is about 3.8 PSI with a non return style regulator, heard some folks using 4 or 5 PSI but it all comes down to if the motor will like it or not.
 
Seems like the spec fuel pressure is close to 5.5psi? Rather than lower the fuel pressure, might lower the float level just a tad instead. As the issue is not fuel pressure, but fuel level being higher than the expanded fuel level would be to start with.

I highly suspect that what you term "flooding" is actually "percolation" instead, where the over-heated fuel bubbles-up as if it were boiling water, then comes out of the bowl vent area of the throttle bores and into the venturi area. Flooding is more constant than temporary, as percolation is only there in hot weather, usually.

Of course, good starting performance is related to how quickly the air flow through the venturi yanks on the fuel in the fuel bowl to get it into the venturis and into the engine. So float level MIGHT affect that a bit, possibly, but as long as the fuel level is at a slightly-lower level than spec, this might not be affected too much?

MANY people have tried to minimize this "hard hot re-start" situation, but FEW have ever succeeded, by observation (and my own experiences with our '66 Newport 383 2bbl and '70 Monaco 383 "N"). And it seems to affect Chrysler products and the 2bbl and 4bbl carbs they used, more than other brands of engines and carburetors, for some reason.

As hood levels became more flat and lower in the later 1950s, it seemed that "air flow around the motor" decreased a bit and could lead to elevated (for back then) underhood temperatures. But carburetors then sat under taller oil bath air cleaners, with more possibility of heat dissipation into the open air. That went away with lower air cleaners and a/c compressors sitting in the way of normal air flow through the radiator and around the carburetor, much less under the intake manifold on B/RB engines (hampered by the "insulator" bag between the intake manifold and the engine).

So . . . perhaps the ultimate way to change things away from the factory design would be . . . to use one of the aluminum plates to cover the block's valley area, use conventional (similar to small block Chevy) soft gaskets between the intake manifold and cyl heads, and replace the normal RV-2 compressor with a Sanden unit OR get the late-'70s a/c mounting bracket kit to move the RV-2 more toward the lh side of the engine compartment (which might also require some additional fabrication, in some cases?). End result should be more open air flow between the bottom of the intake manifold and the cyl block's valley area, for better cooling of the intake manifold (even with exhaust heat going through it), with an aluminum 4bbl intake being better for a 4bbl motor.

That's my theory, at least.

The "insulator bag" has been a bit of a mystery, to me. Some claim it is there to insulate the valley pan gasket from engine harmonics which could make it break and leak oil vapors into the engine compartment. Others have claimed it is heat insulator, having fiberglass insulation in it and a foil-like outer surface. And perhaps it is there to insulate the intake manifold from the cooling affects of air flow under the intake manifold, in colder weather, for better "warmed-up" drivability? BUT it seems it would keep the intake manifold warmer, which might aggravate the fuel percolation issue in spring/summer driving. Which can further aggravate the fuel volatility issues of the current "Gen XV winter gas" we now get in the summer (which is easier to vaporize than the fuels the carburetors were designed to handle, back then). Of course, the "expensive route" would be to do one of the self-learning EFI kits, which should take all of the hot fuel handling issues away in one great swoop, especially now that there are 2bbl EFI systems now.

Take care,
CBODY67
 
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Another possible issue might be related to the ignition system. As soon as the engine turns over, good sparks should be happening, hopefully. Good sparks should ignite any fuel vapors which might be present, less so with "wet fuel" in a flooding situation. The best spark exposure to fuel mixture happen with the old "J-Gap" style spark plugs, where the ground electrode over-hangs the center electrode by only 1/2 or so of the center electrode. OR the later "fine wire" elecctrodes, as current NGK Iridium plugs are, with much greater exposure of the spark to the fuel/air mixture, for a better ZAP and fuel efficiency. Forget the multi-electrode plugs as there is only ONE ZAP per event, which will go to the "path of least resistance". Unless you have a multi-strike ignition system. With breaker point ignition, ensure the points are in good condition and of the correct gap/dwell. An electronic system would be good, too. In some cases, a 50KV coil might help?

Before the fine-wire plugs were readily-available, the original ACDelco RapidFire plugs had all of the known "tricks" in their design. The "cut-back" ground electrode, with a narrower end than the normal width of that electrode, for example. I believe that platinum pads came later?

NGK V-Power plugs were used OEM by Toyota (but not with the "V-Power" name), which is how I discovered them. The ground electrode had a "V" cut into it and it was also "cut-back", in a normal spark plug. As it was a normal-material spark plug, longevity was "normal", too. But I could tell that it worked well, especially8 on open-chamber heads (as the Chrysler LA) engines.

When I first read about the Champion J-Gap Racing Spark Plugs (back in about 1968), I liked the theory and spent about 2 hrs filing the ground electrodes on the J-14Y Champions in our '66 Newport 383 2bbl, then carefully gapping them to the .035" spec. In that motor, I could feel a slightly better throttle response off idle, but that was enough, so I continued doing it with each set of new J-14Ys.

Knowing that some fuel issues can really be ignition issues, it might be best to focus on BOTH rather than just "fuel", it seems, for a better outcome. But I also know that others experiences might be different from my own experiences. So whatever might work best is the "rule of the ages".

So, to me, the default mode is to get the fuel and electronics as good as they can be (i.e., to OEM factory specs) and then tweak from there. But ALSO using the "1/3 throttle" for starting, as our '66 Newport Owners Manual mentions, which I found to work well for all of our vehicles. Just enough throttle for the automatic choke to work (when cold), enough pump shot for a good cold start, and enough rpm as it starts, too. Eventually, YOU learn what the vehicle likes and responds to, rather than the other way around! Not unlike what we used to do in choosing the best fuel brands for each vehicle!

AND, for good measure, as you approach the vehicle, a kind and energetic dialog "Come on, lets go see what WE can get done today" can not hurt, from my own experiences.

Enjoy your Chrysler Products and treat them well,
CBODY67
 
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