307 flooding on startup

[Cimba]

The 307 in my 85 Regal has increasingly been a bitch when starting. Even if you don't touch the gas and even if you touch her light it'll flood out. She'll start one of two ways, hold her to the floor and hope the battery has enough juice to keep it rolling until it catches or pop the breather and put a screwdriver in the carb to hold open the flapper( hi-tech for > I believe it's the choke ). The second works better and either way when she starts the cloud of blue smoke stinks like hell.
Ideas ??

[Twostep]

Choke problem, bro - due to a couple of possibilities.

Could be out of adjustment - but most likely, the choke pulloff assembly is defective. Basically, it overchokes(richens the mixture) to excess and stays that way. Holding the choke butterfly open with a screwdriver allows the mixture to lean, which in turn allows the engine to start. Your 307 either has a Rochester Quadrajet or Duojet (2 barrel) carb, and they'ne notorious for this.

Fortunately, the replacement assembly isn't expensive, and neither is the installation. If you can modify an IRD, you can install a choke pulloff.:)

BLUE or BLACK smoke when starting? BLACK is from overchoking, and will have a raw gas odor - BLUE is oil smoke, will smell like burnt oil, and is invariably due to oil that has leaked into the combustion chamber overnight because the valve guide seals are worn out. Another characteristic of every small-block GM engine (such as the Chevrolet 307) that's ever been built. Not something you need to fix immediately - and it's considerably more involved than repairing that carburetor.

Good luck, bro...:)

[PJMan]

Black smoke=flooding Blue smoke=oil loss this may sound strange, but make sure you don't have the oil overfilled, seen it twice in my lifetime.

[smilingjack]

Why do you think they call them Quadrafloods

Common problem with them for 20 years

[LuckLarry]

He also states "even if I don't touch the gas".If the accelerator isn't touched, the choke won't set past the fast idle cam. This means it could also have "heavy float syndrome".(I know syndrome is a very bad word around here, but I don't give a fuck). Before you start it nex time, have a look past the choke into the air horn and see if there's gas puddling. This was a prob on lotsa old 4gc/2gc quadrabogs from that era.
As stated above though, choke pull-off is a very likely candidate.

[beerbud]

Thats why you should buy a Ford!

[smilingjack]

I guess you are too young to remember all them Fords running around with the paint burned off the center of the hood from them holley's back flaming them

[smilingjack]

Luckylarry is right too, stuck floats were the main reason Quadrafloods got that name, fucking things stuck open and filled them with gas, pedal touched or not.

[mopar611]

Carb is flooding out....

First thing they teach you in auto class is to hold pedal to floor when motor is flooded.

Buy a new carb or rebuild your old one. Nothing wrong with a Quad.. Contrary to belief.. I like them. You can buy a quad rebuild book and gasket set cheap. Tear it apart and rebuild it yourself....

Mopar

[LuckLarry]

Carb is flooding out....

First thing they teach you in auto class is to hold pedal to floor when motor is flooded.

Buy a new carb or rebuild your old one. Nothing wrong with a Quad.. Contrary to belief.. I like them. You can buy a quad rebuild book and gasket set cheap. Tear it apart and rebuild it yourself....

Mopar



Don't forget to replace the POS nitrocellulose float, and both pull-offs if it has 2!I've probably rebuilt 75 or more Rochesters in my long career, and they do rebuild well. For a daily driver GM, I will take a quadrabog over a Holley or Carter ANY day.

[mopar611]

Edelbrock bought out quad.. For one reason, they are good carbs.

I dont like the edelbrocks on both of my pickups. Nothing but problems out wheeling. You get off center and the damn thing want to die. On both of them.

Looking to get a Holley off road or Demon off road.

[keltic]

It is not Quadrafloods its Quadrajunks! I’ve built many more of them then I care to remember and they are notorious for numerous problems. The float is not the only thing that causes flooding in a Quadrajunk. The k-plugs are more of a problem then the float. The best solution I’ve found over the years to solve this is EPOXY. Its amazing how a little epoxy can turn a Quadrajunk into a good carb again. The floats I replace during any rebuild on most all carbs. As far as the nitrocellulose floats, there is a brass alternative out there. That’s what I use. Don’t build many carbs anymore except for performance apps, but then it’s been a long time since they used them on new cars. Now its fuel injectors and throttle bodies. With all that in mind the first thing for you to check is the choke pulloff. Put a piece of vac hose to it and apply a little vacuum. If it starts to open and holds vac then its okay and your problem lies elsewhere.
You know your getting old when you remember rebuilding Stromberg carbs.

[Cimba]

Lots of good input, thanx guys, if come spring and warm weather I am still able it might be a project.

[BirdieMod]

Doesn't around that year have a electronic idle solonoid for the idle jets? May be stuck open flooding it. This is built inside the carb assembly.

[Cimba]

Want my address Birdie and you can come and tell me, lol, I wouldn't know it if I saw it. And forget shop $/hr too, could offer some cold beer. ;) ;)

[BirdieMod]

Beers are always good for me!!!
One of my best friends owns a Salvage yard, So I get parts for free. If you want I can grab another and send it to you if you can or know somwone that can put it on for you.
I'd need you to pm me the motor code number, It's in the VIN number. Or else the VIN number works to cross it to the correct part.

[bobster300]

[quote=mopar611]Carb is flooding out....

First thing they teach you in auto class is to hold pedal to floor when motor is flooded.

Buy a new carb or rebuild your old one. Nothing wrong with a Quad.. Contrary to belief.. I like them. You can buy a quad rebuild book and gasket set cheap. Tear it apart and rebuild it yourself....

Mopar[/quote

but what would u do if ur float is stuck u keep ur foot on the pedal and the fuel keeps on dumping !!!!!!:)

[mopar611]

[quote=mopar611]Carb is flooding out....

First thing they teach you in auto class is to hold pedal to floor when motor is flooded.

Buy a new carb or rebuild your old one. Nothing wrong with a Quad.. Contrary to belief.. I like them. You can buy a quad rebuild book and gasket set cheap. Tear it apart and rebuild it yourself....

Mopar[/quote

but what would u do if ur float is stuck u keep ur foot on the pedal and the fuel keeps on dumping !!!!!!:)


Guess its better to run it rich than lean...:) :) :) :)

To make a long story short, you do know it take AIR and Gas to make a motor run right?? So if its flooding, you need more air to lean it out.

When a float is stuck, the motor will still run. You will either foul out the plugs or get a big puff of smoke on start up. Either or. Thats probably the reason Cimba is having a harder time starting it. The plugs are getting carbon build up.

Thats enough of carb 101 for tonight....

Mopar

[racer55]

not sure if its an old wives tale or not but I was once told that after flooding the spark plugs are only 1/2 as effective as they were new,even if they were new the first time flooded.
any thoughts on this?

[Texas Trophy]

not sure if its an old wives tale or not but I was once told that after flooding the spark plugs are only 1/2 as effective as they were new,even if they were new the first time flooded.
any thoughts on this?

Depends on the plug. Most of them will clear themselves provided that the engine is running properly. The only plugs I have run into that once they are fuel fouled, they're done, is Champions.