I have a 1965 425, newly rebuilt (before I purchased it), has less than 50 miles on it. A heads, Performer, Edelbrock 750 with electric choke, new Pertronix Ignition, Hooker Headers. It had been running fine, although I have never driven the car anywhere outside my neighborhood. Yesterday I was going to go and get some gas. It fiered up easily, and I started driving to a nearby station. I stopped at a light, and on the green I started off and it bogged down and died. I cranked and cranked and it would not start, wouldn't even try to start. I used the starter to move the car out of the intersection. Called the wife for jumper cables and gas can, as I thought maybe I had run out of gas. Put some gas in, hooked up the cables, it cranked fine but it still wouldn't start. I took off the air cleaner and poured a bit of gas down the carb. Cranked it and was able to get it started after quite a few cranks. Drove it home and cussed at it a bit and left it to cool off (me that is, motor runs a steady 190 deg.). As I was driving it home, I noticed that it was not charging. Today I put a rebuilt alt on it and it fired right up and is charging fine. I let it warm up, it is running fine, but seems to have a hesitation off idle that I haven't noticed before. I think it was doing it yesterday as well, and that is why it bogged when I began to take off from the light. I turned it off and tried to start it again. Same issue as yesterday.......... grr........ I put some gas down the carb, cranked it some and it started. The electric choke seems to be functioning properly as the butterfly opens as it warms up. Fuel pump is brand new, as are all of the gas lines, and there is no filter in the line from the pump to carb. I'm stumped. It starts fine when cold, but not when at operating temp. I have had no experience with Edelbrock carbs at all, but I'm leaning that direction....... Thanks in advance for any guidance................

 

Hi Randy - Reading your issue(s) statement(s) it appears you found & resolved one issue - the alternator. It would appear the alternator went out on you & you were limping off the battery alone (lucky you got home I think). You said it's charging fine on the new rebuilt alternator. You should be getting ~14.3V - ~14.7V at the battery when charging - is that w/in the range you measured? It sounds like you may have a fuel issue, as well? Not sure. You said fuel pump is brand new. Do you have a mechanical fuel pump or electric fuel pump? I'm guessing electric & the fuel issue is somewhere tied into the dead alternator's failure to keep up with amperage demand via the car's modifications? I don't know about this for certain, but if you'd been running on a super weak alternator for an extended period of time - essentially limping along since alternator could not supply the demand for current (amperage) - you may want to do a serious double check of your wiring - starting with your ground wires from battery to engine, chassis & frame. If the demand for amperage continued to exceed the alternator's output, you may have increased resistance in your wiring - especially at the terminal ends. Heat builds up, resistance increases, no amperage gets delivered. Bottom line - I'd perform a serious check of your electrical wiring at this point - simple issue if you find one or several terminal ends have serious corrosion, galvanization, etc.

 

E-Brock carbs are prone to vapor locking on todays fuel. If you don’t have one already, try a phenolic spacer between the carb and intake. It made a big difference on my car.

 

Hi Norm,
Manual Fuel Pump, this car was a frame off resto, all wiring is new, ground straps in place. This issue just developed.

 

This issue just started yesterday, car has not had this issue before............ that's why I'm stumped...........

 

I'm hedging my bet on wiring or at least an electric device tied to ignition wiring - some place - I do not know where, but that would be my first choice of troubleshooting. When a wire gets hot, metal atoms vibrate vigorously - quite vigorously. When metal gets hot and remains hot the resistance increases substantially meaning it's difficult to pass current (amperage) through hot metal. Car fires up normally with cold wires, but fails to fire up with (I suspect) hot wires (or some device which is overheated or impeding current). Something along the wiring circuit is remaining hot - just my guess, but I'd check wiring.

 

I follow your thinking, but as I mentioned, all of the wiring is brand new, new ignition switch, new electronic voltage regulator, new mini starter, and ground straps in place. The motor ran great until yesterday........ why would the motor fire after adding fuel thru the carb?

 

I am hedging along the lines the alternator became a part & partial contributor to your issue - for whatever reason - the fact the alternator went South on you the same time you have now developed an inability to start when warm leads me to suspect electrical & not mechanical - I doubt the two together were a coincidence but rather tied together to your warm engine no start issue. There is no need to dump fuel into the carburetor to start the engine when the engine is cold - this is what I believe you've suggested thus far, correct? On the other hand, the engine won't start when warm - but if you dump fuel into the carburetor the engine starts and continues running for an extended normal period of time. Why would the motor fire after adding fuel thru the carburetor I don't know unless the surely (not normal) overabundance of fuel added through the carburetor lessens the burden of the electrical system to fire off the engine since obviously enough heat added to fuel will ignite fuel without any electrical input. I'd measure your alternator output to ensure it isn't above 15.0V when charging & I'd still check your electrical connections for tightness at least. Even with a frame-off resto, new everything, one critical bolt loosening up is enough to create havoc on starting - air is the greatest insulator - electricity doesn't pass through air. A loose bolt can make you lose your mind. Good luck!

 

Check the plugs and see if they are carboned up, also check your timing.