Car does not start after running 20 min.

[cmesa]

The right side of the exhaust does not have a shield. I am going to replace the pump this weekend. As far as the fuel hose, its new, I replaced it when I changed the carb. I have metal tubing to about 2 inches before the fuel filter and from the filter to the carb its a metal line. I replaced the gas tank and put in new vent hoses. After I change the pump I'll post the results.
Thanks to everyone

[RDF]

Did you check the ceramic solinoid (I can't remember if it's a solinoid or not) but it sits on the firewall and mopars are notorious for these things heating up and not allowing the car to start.

[cmesa]

Actullay I did notice that the cermic part on the firewall does get really hot. I have no idea what that does but its gets HOT.

[matt63]

I think you are talking about the ballast resistor.  If it fails the car will start but won't run.  It's resistance can be checked.  It should be around 1 ohm (0.8 to 1.3).

[RDF]

That will probably be the cause then.  Autozone or another LAS (local auto store) should have one, they are pretty common.  

[RDF]

I think you are talking about the ballast resistor.  If it fails the car will start but won't run.  It's resistance can be checked.  It should be around 1 ohm (0.8 to 1.3).

My Cuda was just the opposite....it would start, run fine, then once that ballast heated up and I had to shut the car off, it wouldn't start again.  Only after cooling for 30+ minutes would it start.  I replaced it and it hasn't done it since.

[cmesa]

What would cause the ballast to heat up. I recently changed the coil.
Thank you

[matt63]

Ballast resistors do get hot as they are dissipating heat.  I'm guessing that most failures occur when the wire coils eventually break.

[MEK-Dangerfield]

Ballast resistors do get hot as they are dissipating heat.  I'm guessing that most failures occur when the wire coils eventually break.

Right you are.  They expand when hot, then contract once they cool. Do this a few thousand times, and it eventually snaps. Just a note because I know of this from my car, the resistance can rise before the breaking point, giving you a weak spark. I had a weak spark problem, it turned out my ballast resistor was measuring 2.4 ohms.  I couldn't start the car below 40*F. It took me a good while to find that problem. 


  Mike

[Chryco Psycho]

A higher output coil can put a higher load on the resister causing it to fail 

[Bullitt-]

OK guys my spidey sense is giving me something....in the first post it was stated that he could see that fuel was not flowing through the filter...if this has a non-vented gas cap does it not sound like a vacuum could be being created in the tank?    If so simply removing the cap next time the trouble shows up & see if things clear up will be easy proof.(maybe hear a swoosh when you open it)  Solution change to a vented cap or drill a small hole in the one you have. 

[cmesa]

The gas cap is vented, I thought about that too, so I opened the cap but had the same outcome. What I noticed is that the fuel filter starts emptying slowly, till just a trickle flows in.

[Chryco Psycho]

If ti si a big block is the fuel pump pushrod worn & not cycling the fuel pump fully ?

[cmesa]

Well my problem was not solved with a new fuel pump. Actually its worsened, now the fuel filter does not even get half full. At least with the old pump, it would initially fill up and then as the car ran for a while it would start to get less fuel, till it was almost empty. I  called the tech number on the new fuel pump and a tech. told me that it was probalbly related to fuel vapors, or the fuel lines where getting hot. WHAT A PROBLEM I'VE BEEN AT THIS FOR A GOOD WHILE.
THANK YOU

[6packCuda]

Did you check the fuel pump push rod like CP said? I had a very similar problem a while back and the push rod was to blame.