Interesting turn of events

[Skytrooper]

Ok, Lets back up to Labor Day weekend. The car (71 440 charger) is running very nicely. I decided to take it around the property a couple of times. It is still running well, although it almost stalls in gear. Anyway, since this is its first time moving under its own power in probably 10 years, I drive it around a bit then put it back in the garage before the neighbors call the cops from the open headers. I am quite pleased and ordered an exhaust system for it. Now when I try to start it if it even starts at all, it stumbles and quits. On occasion it will spit out of the carb (getting too much fuel ?) or I get a purty flame from the carb. Nothing has been changed with the timing or the fuel system since it was running so well. Only the exhaust, which does not appear blocked or restricted. The times it has started for a few moments it sounded very nice.
Specs:
440 RB with correct AVS carb
carb rebuilt before installation
Electric fuel pump, no mechanical pump
All new fuel lines from the sending unit (also new) to the carb. Tank was out and totally cleaned.
I do not have a choke of any kind installed

There is no control on the fuel pressure from the electric pump, but like I mentioned previously it had been running great.

Any thoughts ?

 

[moparedtn]

If she's barking through the carb, that's usually timing, right?
I've seen them do that from being really lean, too...like with a cold start
and no choke?

 

[Skytrooper]

Thanks for the reply Ed !
I have not changed the timing since it was running, but I do not have a choke of any kind on it.....and it is a cold start (only about 50F right now). I did have the choke plate held closed and that was when I got the flame.

 

[493 Mike]

Perhaps rust from the fuel lines got into your rebuilt carb?
Mike

 

[Skytrooper]

Mike,
All is new from the sending unit to the carb. I had the tank out and cleaned it out completely too. Thanks for the reply

 

[oldbee]

Old gas? Probably dirt in carb.

 

[Darter6]

Is the fuel fresh ? Kern Dog posted awhile back he was having problems with his car not running.Said fuel was several months old.Put in fresh fuel and the thing ran great. Just spit ballin'.

 

[1 Wild R/T]

It doesn't like having mufflers???? LOL

Actually somewhat seriously, any chance the pipes are slid to deep into the mufflers? Any rodents around that might have filled the mufflers with nesting material?

When you exhaust is plugged the engine barely starts & when it does it'll fart back through the carb when the back pressure causes the engine to die....

 

[Fran Blacker]

If carb was rebuilt 10 years ago check accelerator pump shot, if you get a good shot not your problem. This spring my car had same symptoms. I could get it running but kicking back. Accelerator pumps on both carbs dead, ran ok when I put it up for winter. Carbs hadn't been touched in 40 years. The kicking back killed bendix, more work.

 

[turbine68rt]

Are you running points or electronic? If points, dwell and condenser good?

 

[Skytrooper]

The fuel is all nice fresh 90 octane no ethanol, a full tank. Carb was professionally rebuilt this spring and has been functioning great. The exhaust I installed. I marked all the pipes so I would not install them too deep. When the car actually started a couple of times on Thursday, nothing blew out of the exhaust and it sounded good. It is all 3" from the headers back. It would start, but not stay running for more that a couple of seconds. I am a bit baffled. I hate to start fiddling with the timing since it was running so well.
I am running old school dizzy with points and condenser...all new also.

 

[turbine68rt]

If the points were changed, the timing should be rechecked since the gap will affect the timing setting.

 

[oldbee]

Trooper you're not helping,lol. Getting a good spark? Pull top off carb?

 

[440Coronet500]

You need new neighbors! 440'

 

[Fran Blacker]

Got a fuel filter inside carb inlet.

 

[1 Wild R/T]

Try running it on carb spray... If it can be kept running then you have a fuel problem... If not it could be ignition, it could be mechanical but not likely..

 

[Skytrooper]

Ok, I have been playing around with it for the past hour or so. If I use a piece of wire on the choke lever to hold the choke closed, it will start up and run. However, once I take the wire off it will pretty much die. If I leave the choke on too long I start getting pops/bangs in the exhaust (too rich/unburned fuel ?).

If the points were changed, the timing should be rechecked since the gap will affect the timing setting.

I have not changed one thing since it was running before. I have not adjusted anything either. It was running great and driving without issue

Got a fuel filter inside carb inlet.

Yes, it does have the inlet filter.

Great responses gang ! I appreciate everyone's help !

 

[moparedtn]

Without a working choke, she's dead lean on start-up - and now that it's cooler, perhaps
that's enough to cause what you're describing. When you crank it up, can you keep it
running by throttle?

I always have had the bad habit of disabling chokes on my cars, hate the things.
That means I have to "babysit" the car by gas pedal for a couple minutes until it gets
enough heat in it to idle on its' own, which is fine by me.

I don't get pops back through the carb though - that still sounds like timing to me,
perhaps exacerbated by the lean condition at start-up?

 

[moparedtn]

You need new neighbors! 440'

Wish I lived nearer to him, I'd be over there helping in a heartbeat!

 

[dadsbee]

Fill a water bottle with fuel, put a 3/32 hole in the lid. Fire her up and see if she'll keep running on some throttle play and the odd squirt of fuel. If she'll run you have a fuel delivery problem, pump, fittings, filter or stuck power valve. I'd start by taking a line off and putting it into a can and turn on that electric pump to see if it's really pumping..