starting issue carb or not

[backrodebob]

I have a Holley 390 on an 8ba it will start then dies? I'm at my wits end!
I've tried everything I can think of and it's still doing the same thing. Need some help from you Guru's out there

[Ricosan]

Definitely sounds like a fuel delivery problem. Have you checked the output of the fuel pump?
Undue the fuel line from the fuel pump to the carburetor. Have someone hold a water bottle over the outlet from the fuel pump and turn the engine over. Fuel should flow into the bottle if the pump is working properly.
Richard

[Terry,OH]

Is this a new issue or is this the cars first starts? Did you do ignition work?

[scicala]

Need more details on what you did to get at your wits end. Has the carb or anythng else just been installed ? Was it running good previously ?

Sal

[backrodebob]

fuel Pressure is 7psi disconnected fuel line and fuel is definitely coming out. This has been an ongoing issue?! rebuilt carburetor, changed fuel filters and ck’d for vacuum leaks.

[marko39]

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Is engine getting flooded? How do plugs look after it dies? Fuel pressure seems higher than you need.

[47topless]

Originally Posted by marko39

is engine getting flooded? How do plugs look after it dies? fuel pressure seems higher than you need.

[backrodebob]

talk to holley that was there recommendation? and it’s not getting flooded new plugs and they look good. checked coil and as long as I keep my foot on the gas I just keep it running till the warms up a bit and then it’ll run perfect. should have included that in my original post

[Don T]

and the choke?

[backrodebob]

new choke

[baceves]

When starting your car is the manual choke fully closed, halfway or entirely open? Understanding how to use the manual choke can make a huge difference. For me, I always use to have issues initially starting my 47, but once I understood how to use the choke and how to pump and feather the gas pedal while starting has solved my issue. I start my 47 once a week and with what I have learned in regard to the manual choke my car starts immediately on the first try now.

[ponymare]

If it starts then dies instantly, sounds like you're loosing fire.

[FlatheadTed]

Dirt in idle jets ,strip carb down and blast out with 100 psi air , or Vacuum leak in the manifold spray some starter fluid around ,

[Flathead Fever]

I agree with "ponymare". If it starts while cranking and then dies the second you release the ignition switch it could be a burned-out ballast resistor, if it has one. If it was wired like most factory 12V vehicles were like mustangs, in the crank position the coil is given a full 12 volts from the starter solenoid. This produces a hotter spark for easier starting. When the key is released back to the run position the voltage then goes through the ballast resister. If the resister burns out the coil will not get any voltage in the run position. We had a lot of Dodge vans in the phone company fleet that took that same external ceramic resistor a lot of hot rodders use them. It was fairly common for them to fail. They ran while you were cranking the engine and quit when you returned the switch to the run position. One of the fastest fixes and repairs you can diagnose. If you have the external resister bypass it an see if it will run. Don't leave it bypassed for too long or it will burnout the coil.

If it's a fuel problem, you can spray starting fluid, carb cleaner or brake clean into the carb to keep it running after it starts. If it runs on the spray cans you know it's a fuel problem. If not, it's an ignition problem. Does that Holley have a site plug for the float bowl level.
If it was fuel it would not instantly turn off after it starts, unless it was only running on the squirt from the accelerator pump and then not getting any more fuel There is a difference between how an engine quits if it runs out of fuel or runs out of spark. Just that a couple seconds of sound usually send me in one of those directions. Its 45 years of hearing the differences and sometimes still jump to conclusions and am wrong. What's important is when this fixed you will be a better mechanic. I admire people that work on their own cars. If you can fix cars, you can fix most things. The most important thing is to understand how each system works. The fuel system, the ignition system, how basic electricity works... That is the key to fixing this stuff. None of it is hard if you're interested in it.

Don't overlook coincidences. You can put a new carb on and have the resister burnout at the same time. The "universe" loves to mess with mechanics. I have had some really weird coincidences happen during my career that made me glad I was working on fleet vehicles and not on customers vehicles. W' called it drive them in a push them out at work. we were thinking, all I did was change the oil and now the trans won't move. Really, you wait until I sit in the seat to break!

I was thinking about this some more. It could possibly the ignition switch could be bad; I only saw it happen a few times in my career. Just like the resistor, the clue would be that it instantly shuts off when it returns to the run position. You can jump 12 volts directly to the positive side of the coil for just a minute or two and bypass the entire switch, resistor and wiring and then crank it. If it starts you won't be able to turn it off without removing that wire. I have a arsenal of different gauge and length wires with alligator clips for bypassing stuff. It' not a bad ideas to carry one in your emergency tool kit.

[flatford8]

“checked coil and as long as I keep my foot on the gas I just keep it running till the warms up a bit and then it’ll run perfect. should have included that in my original post”.........Mark
P S......I’m with baceves.....experiment with the choke......don’t open it all the way to soon....

[backrodebob]

thank all of you for the input! choke is electric, I rebuilt carb and coil, condenser and ballast tested good. now you see what mean by at wits end��www.jalopyjournal.net♂️

[Flathead Fever]

That electric choke is adjustable. You can adjust how much it closes and how fast it idles when it's cold. Then when it's warmed up and comes off of the choke I would adjust the air fuel mixture screws. It might be too lean and adding to the cold drivability problem. When it's warmed up run a slightly opened propane bottle over the top of the carb. If the idle goes up it is set too lean, if it goes down it is set to rich. It doesn't have much effect your idle air fuel mixture is at the happy spot.

Holley electric choke adjustment video.

https://www.youtube.com/watch?v=4BTiXcMHdXM

[JayChicago]

I also have a Holly 390CFM carb with electric choke on my flat rod. When engine first starts, vacuum to the choke housing opens the choke somewhat. My flathead doesn’t like that, still wants lots of choke, engine dies. I have to pump the pedal to squirt extra fuel to keep mixture rich. After about 30 seconds it idles fine. I adjusted the choke to be overly rich. Better at start up, but then too rich after that first 30 seconds. I don’t think there can be a perfect adjustment. I am going to convert to a manual choke.

[backrodebob]

I think I’m go’na do what Jay Chigago’s go’na do convert to manual choke!! THANX FOR ALL THE INPUT