Re-starting issue

[mopar thunder]

My wifes Cuda has a starting issue after she drives it. Here are the newer items on it;

Comp Cam 273/491, Holley Street Avenger 670 carb, Airgap intake, water pump, new fuel lines, pump & filter, wiring harness, new starter, radiator 4 core aluminum, new distributor, ignition ballast, and coil. Timing on the car is good.

Car starts right up, idles perfect, never stalls and stays cool however if she drives it a distance (ex. 20 minutes) and she shuts it off say for at least an hour when she goes to start it back up it won't start. It has to sit for a long time. What might be the problem?  Vapor lock....... electric choke issue..... carb float issue....  do you think it is boiling the fuel after it shuts down and is self flooding?

I even tried ether and it didn't react at all, did absolutely nothing.

[70 Challenger Lover]

My wifes Cuda has a starting issue after she drives it. Here are the newer items on it;

Comp Cam 273/491, Holley Street Avenger 670 carb, Airgap intake, water pump, new fuel lines, pump & filter, wiring harness, new starter, radiator 4 core aluminum, new distributor, ignition ballast, and coil. Timing on the car is good.

Car starts right up, idles perfect, never stalls and stays cool however if she drives it a distance (ex. 20 minutes) and she shuts it off say for at least an hour when she goes to start it back up it won't start. It has to sit for a long time. What might be the problem?  Vapor lock....... electric choke issue..... carb float issue....  do you think it is boiling the fuel after it shuts down and is self flooding?

I even tried ether and it didn't react at all, did absolutely nothing.

I think it's the last. My cars get this too. I think if it sits long enough, the fuel that boiled out into the manifold eventually evaporates so the carb is essentially dry until the fuel pump fills it again.  It's the crappy ethanol blended gas that has a lower boil point. There are things you can do that help. My next build coming up, I'm going with an EFI conversion. What I do with my current cars is crank and crank until it starts. Sucks.

[Brads70]

If it is boiling the fuel out of it you might try a insulating plate between the carb and intake, failing that I have an electric fuel pump and a return line right up to the firewall so carb is always getting cool fuel.
If it is flooded did you try holding the throttle wide open and starting?   

[dodj]

do you think it is boiling the fuel after it shuts down and is self flooding?

Yup. I'm willing to bet it will start right up a minute or two after shutdown. But after that it will be flooded and will have to sit for a while for the gas to clear out.
Try taking the air cleaner off immediately after a 20 minute cruise and peering down the carb. I'll bet the throttle plates will be getting wet.
Challenger Lovers suggestion of efi is the best remedy, but a bit pricey. You could try a carb insulator or maybe take off the intake and use gaskets that would block the coolant port in the middle of the head. (unless an air gap does not have the crossover? Not sure)

[MoparLeo]

Best advice that I can give is to verify the problem before you start throwing things at it. If this problem is consistent and repeatable I would start by checking the carb for fuel before restarting by looking down the carb and operating the throttle to check accelerator pump is working.  If not, make sure bowls are full . I use a plastic squeeze bottle with a small hose attached that will fit the vent tubes.  If they are empty/low check for heat evap with an infrared temp gun at the carb base . Heat sink with ethanol fuel blend ( a lot of gas stations use it, check the pump stickers where you buy your gas ) can cause quick evaporation. If not, keep checking the fuel system. Fuel pressure, fuel filter, fuel lines, connections etc...If the bowls are full and accelerator pump is functioning properly look at the ignition system. Just diagnose it step by step, obvious things first. Don't just start to replace things.

[worthywads]

I have a Holley Street Avenger 670 and I was having similar issues and it ended up being loose screws on the accelerator pump letting gas drain from there.  It originally had an accelerator pump that had rubber that wasn't made for ethanol.  I replaced it with one that can handle ethanol, I think it was this one.

https://www.summitracing.com/parts/hly-135-15?seid=srese2&utm_source=bing&utm_medium=cpc&utm_campaign=Brands+|+H&utm_term=4581939832668461&utm_content=GSAPI+5ba272f94185f

[mopar thunder]

Thanks everyone for your input and guidance. It is frustrating. I will try the elimination route. I wish we could go the EFI route right now but unfortunately the debacle with my car just doesn't allow it. I'll check for hood clearance to see if I can get a plate in there. The accelerator pump I have seen done before so that is an option.

Has anyone ever used a heat disappator spacer?

[Cuda Cody]

When it doesn't start does the starter turn over fast or is it a little slower than normal?

[Racer57]

I had issues like yours that was from fuel boiling out on my stock 383. I put a fiber spacer under the carb, routed the fuel line so that it did not touch any part of the engine and wrapped fuel line isolation from the carb to where the line made its turn to head towards the tank. That took care of the problem. 

[YellowThumper]

Same issue with mine as well. The fuel would boil out. You get a combination of fuel in ports and dry carb. Insulator can help. Now have ele pump with return system. Carb gets primed with fresh fuel as soon as key is hit. Cured my issue.

[GrandpaKevin]

I had a similar issue years back.
Spent hours troubleshooting fuel and carb with no luck.

Finally had an old time Mopar tech tell me to change the magnetic pickup in the distributor, yes they do go bad.

They work fine when cool then after being driven and getting warm with engine temp they would fail and not work when trying to restart until it cooled down.
If you have electronic ignition I would suggest swapping out the magnetic pickup first.

[Chryco Psycho]

Just for giggles confirm you have good spark when it does this , just carry an extra spark plug & connect it to the coil wire & ground it & crank it over to confirm spark , it seems odd that it will not try to start with ether

[73440]

I had issues like yours that was from fuel boiling out on my stock 383. I put a fiber spacer under the carb, routed the fuel line so that it did not touch any part of the engine and wrapped fuel line isolation from the carb to where the line made its turn to head towards the tank. That took care of the problem. 

I did the same two things and that took care of my starting troubles like yours also.
DEI Heat Sheath Protective Sleeve is what I wrapped the fuel lines with .

[torredcuda]

Check needles and seats, they get worn and will leak down and empty the bowls when sitting for a while. I had the same issue with mine, new fuel seems to make them wear quicker.

[mopar thunder]

CudaCody - The engine does turn over as normal. Doesn't slow down at all.

Racer57 - Thanks for the info. The car doesn't have headers and the fuel line is in the stock location along the frame then to the fuel pump and behind the alternator to the carb. Not to close to the block. It's such a simple system.

Yellow Thumper - An elecric pump is an option on our list.

Chryco - I agre, seems odd there wasn't any type of reaction when ether was sprayed.

Thanks again everyone, process of elimination time.