Cold Start Flooding

[55 Fargo]

Hey, anybody have an idea on this one.

I have been finding my 47 getting flooded easily on cold starts, and sometimes when at operating temps too.

I have my float set fairly low, at about 1/8 inch below the bowl edge, my float retainer clip is in snuggly. I have had the carb top off a couple of times this past week, and the fuel level is as per the float, nothing spewing out.

The choke closes nice and tight on cold starts, verified this.

So what is going on here, I have mentioned this before, but have lived with it, but would like to find a solution, anyone got any ideas....Thanx Fred PS is this fuel or fire, it does fire, when starting, but I have to floor gas pedal to clear carb and get started.

[Young Ed]

Fred only an 1/8? Isn't the spec 5/32s? Correction its 5/64s.

Edited April 26, 2011 by Young Ed

[55 Fargo]

Fred only an 1/8? Isn't the spec 5/32s?

Yes I believe so Ed, I was going by how Greg G set his carb float height, maybe too high still?

[Young Ed]

Greg says to lower it not raise it. So I'd lower it a few 32nds.

[55 Fargo]

Spec on my Echlin rebuild kit and Chrysler shop manual states 5/64, so 1/8 is 8/64, so I am below the suggested float level height...

[Young Ed]

In that case you are right Fred. I remembered the spec wrong. I would think an 1/8 is good then.

[Reg Evans]

Could be that you are just pumping the gas pedal too many times before it fires up?

[55 Fargo]

Could be that you are just pumping the gas pedal too many times before it fires up?

Nope, just bearly touch it to set the choke, if you pump it, it floods, just like that....

[Merle Coggins]

Have you tried to start it without setting the choke? I've found that my truck will usually start without closing the choke (manual choke). It seems to flood if it is choked for startup unless quite cold outside. On cooler mornings I may pull the choke our some after it starts, but it seems to start better without any choke. I've never looked into it to see why, I just live with it. Maybe my idle circuit is rich enough as is.

Merle

[cwcars88]

Try hitting the starter first, if it doesn't fire then one pump to give it a shot of gas and set the choke.

[55 Fargo]

Okay, it is a scisson auto electric choke,not a manual choke( 47 C38 Chrysler) so it sets very easy. I have ried all the methods ever suggested, but often get a mildly flooded carb, where I have to floor the ghas pedal to start. This happesn sometimes after a drive to operating temp, then shut off to get gas for example, then it gets flooded easy sometimes too....

[TodFitch]

What adjustment hole do you have the accelerator pump set on?

[55 Fargo]

The middle for summer type use, the carb was rebuilt by a reputable mechanic, that knew old skool carbs...

[Tom Skinner]

Rockwood,

Does your Temperature Spring hold the Manifld Heat Control Valve/Riser Flap in the correct position? The Service Manual Booklet "Engine Power & Economy" Volumn 1 No. 12 August 1948 on pages 16-20 discuss the importance of the position of the Valve a picture on Page 16 show the Valve Stop's correct positioning (when Cold) so the mixture/temperature is correct for starting - whether cold or hot. In addition to this a real "Rich" setting might be the culprit as well. Go to The WPC Club Website (www.wpcclub.com) see Technical Tab will show you the entire Booklet if you don't already own one. I just changed out my Manifolds (They were rotting and leaking) and when I re-installed my Valve Stop correctly it fixed my flooding when Hot problem and now when cold it starts like a Gun Shot.

Its Critical That the Spring is wound conterclockwise as the instructions walk you through this pay particular attention to the Valve Stop position on the Weight.

Tom

Huntersville, NC

[Niel Hoback]

I really doubt that the manifold heat valve could have any effect on cold starting. There is no heat available open or closed, and it has no connection to fuel flow.

[Tom Skinner]

Neil,

You may be right. There probably is a smaller effect when cold, however, why has my problem gone away? The Valve may not have a valve stop left on it - either worn away or rusted off. When that happens and the spring is cold the Flap/Valve is too far open and exhaust doesn't help the function which to some degree determines the fuel molecules reaching the cylinders in the right "suspended state". I would read those pages I suggested in that Booklet above because installing a new Stop correctly has seemingly fixed this problem for me. I believe it is stated as: "Its function is to preheat the air-fuel mixture delivered by the carburator so it will reach the cylinders in a vaporized state and be more efficiently converted to power through more complete combustion". In addition "watch the movement of the thermostat shield when the engine is quickly accelerated". "If the thermostat shield moves about a quarter of a turn when quickly accelerated the unit is working as it should". (Engine Power & Economy) Service Reference Booklet August 12, 1948 Volumn 1 Number 12. If the Valve stays closed as when cold vaporization of the mixture is not complete. " The Gasoline would be drawn into the cylinders all right but might not burn, Instead, that unburned portion would find its way down into the crankcase and dilute the oil".

[Niel Hoback]

The position of the flap cannot affect the fuel mixture during a cold start. There is no heat available on cold start. It would make no difference during cold start if the flap was missing completely. After the engine starts there is some heat available to warm the bottom of the intake manifold and then help atomize the mixture aiding cold engine performance.

If you have a flooding problem, don't be distracted from the real prooblem by a malfunctioning manifold heat valve.

[55 Fargo]

My heatrriser works great and ius rebuilt.

This problem seems like fuel but could be fire, not sure, but it is always there....

[55 Fargo]

Okay, tonight I had a hard time starting my engine,. after 5 minutes when I went to get gas.

The engine temp was not hot, about 160, it is a cool night here so underrhood temps are low.

I pulled carb top, float is working well, and checked out okay, needle was clean and woking holding back fuel.

So what is going on here, is this carb toast, and time fo ra new one.

The carb is super clean, was rebuilt a few years ago, but I am not getting anyhwere on diagnosing the hard start and easy flooding, especially when the engine has been driven and warmed up.

Do I need another carb?

This is a pain in the butt, as I almost did not get this engine to clear and start while out tonight, once started she ran well.

The gas tank was brand new 3 years ago, I run 2 fuel filters, carb rebuilt, all new lines and hoses, so don't think any foreign material is my problem.

Sorry to keep bringing this up, but I need to find a solution to this problem.

My fuel system is not displaying any fuel pump issues, that I can identify.

My ignition system is in good order, newer everything including the coil. The engine runs well,except for the hard start crapola......Thanx Fred

[aero3113]

Fred, how is your battery voltage? If it is low, the spark may not be strong enough to light the fuel right away.

[55 Fargo]

I dunno, it cranks very well, and starts once fuel has cleared carb.

I am not ruling out what your saying, but my battery seems to be putting out the juice, I runa trickle charger on it, and it goes to full charge quite quickly when hooked up.

I strted the engine 15 minutes ago, started like nothing, went a very short drive, shut her down, then restrted very easily again, so hell I don't know, this is getting frustrating, I hope I can discover the glitch, as I don't feel like stoppping anyhwere, when I take this beast out....

[meadowbrook]

Hi.

I wonder if your carb was improperly rebuilt. Even experts make mistakes.

Maybe it's time you had a crack at it. It's not hard if you follow instrctions and are careful. Maybe there is a part missing or loose inside.

Also, are you sure it is flooding? Do you smell gas when it floods? Does it idle smoothly and responds to the throttle crisply? How's your gas mileage?

Have you adjusted the idle mixture properly?

Just some thoughts.

[55 Fargo]

Hi.

I wonder if your carb was improperly rebuilt. Even experts make mistakes.

Maybe it's time you had a crack at it. It's not hard if you follow instrctions and are careful. Maybe there is a part missing or loose inside.

Also, are you sure it is flooding? Do you smell gas when it floods? Does it idle smoothly and responds to the throttle crisply? How's your gas mileage?

Have you adjusted the idle mixture properly?

Just some thoughts.

Not sure if was rebuilt improperly, as it so simple but who knows, can re-do it myeslf, but really what is there to it. The carb is super clean, the airhorn is not warped, so what do I really need to rebuild, another needle, the float looks good, the accelerator pump is working.

The engine performs well, accelrates very well, fuel consumption seems normal.

It is just this friggin hard to start problem after a drive, and it gets warmed up.

I smell gas, but it is not pouring out the carb, you have to floor the gas pedal to get it to start and clear itself, it sometimes idles rough for a few minutes after an episode like this, tonight it idled fine right after It finally started....

[55 Fargo]

Hi all, I have tried the folllowing on my Carter B&B Carb.

I have recenlty pulled the float, to verify it is not leaking, and it is not.

The needle when I removed it, was very clean,. as is the carb bowl.

I also adjusted the accelerator pump linkage to a summer setting on the shortest stroke, I had it set in the middle setting prior.

I have now experienced easier warm and cold starts.

I am able to shut down the engine, once warm and have not had trouble restarting it afterwards.

We have not had hot weather here the past week, so that will be test, on a hot summer day.

I also made sure my fuel lin from the fuel pump, is not touching the engine,oil pump, or anywhere near the exhaust manifold.

So we shall see if this problem is corrected or not in the coming days...

[P-12 Tommy]

Fred, I've noticed in the hot Florida weather I've had to adjust my float about an 1/8th lower for expansion. I still think about the float retainer clip moving around, if you know what I mean.

Tom