I purchased my first corvette about a year ago ('78, L48, silver and black, was all original) and had no issues up until a month ago. The original transmission went out and I had decided to rebuild it myself but right after I finished and put it back in I decide that I wanted something that could take a little more punishment so I moved to the T400, knowing I had to make some modifications; speedo line, kickdown, etc. After the installation everything worked great...for about 30min, after which time my car died. Thinking it was because I had left it on a minor incline (10-15°) I thought the fuel had settled back away from the pump, and was unable to feed the engine, but after placing it on a flat surface that thought quickly vanished when I was still unable to get the car to run without a constant feed from an over carb fuel source. I have troubleshooted and replaced some small parts such as the fuel filter and sparkplugs, and still came up with nothing. Right now I think I have narrowed it down to two possibilities; the fuel pump, or the carburetor. If you have any insite on possible issues I will be grateful for all suggestions. I am new to the carburetor engine and thought it to be best if I asked a public with a better knowledge on them than I before making any final decisions. Thank you for your time.

 

So it sounds like the car is having fuel starvation issues. Don't worry, most classics encounter this from time to time. Eventually you should find the problem. Your carb's venti passageways in the carb might be clogged. If you haven't done so already, I would get some carb cleaner, starter fluid, etc. You may have trash in the fuel line of the tank. The tank might need to be drained and flushed. Fuel pump might be an issue, but could it be that your spark plug wiring orders are out of order? Your carb might need to be rebuilt, and I had to rebuild mine Q-jet 3 times in less than a year. Make sure that your are using proper premium fuels. Carbs from yesteryear don't appreciate the low grade fuels of today with ethanol. IT gums up the carbs venti ports. I am pretty tired so this may not be of much use, just landed in the Cessna, but hopefully this will help some.


on finding the problem

 

More than likely could be the fuel pump. Are you getting fuel to the carb? Are you getting a shot of fuel when you pump the throttle? If no then trace your way backward. As pointed out, the carb could be the culprit.
You stated that you replaced the fuel filter and it ran after that ...right? The next thing in line is the pump. The diaphragm in the pump may have ruptured so take the fuel line loose and see if when you crank the engine you are getting fuel. (keep away from spark source) If not it probably is the pump. If not the pump then check for constricted fuel lines or trash in the tank. Good luck and let us know how you make out.

Fred

 

Thank you for some ideas on what to look for. I'm headed there right now to look at the car, I'll get back if I find what's wrong.

 

Take some photos and post them of the cars motor and carb. We might be able to spot something out of place.

 

Pull the fuel line off the carb coming from the pump. try to start the car and see if fuel is coming out the line. if not, then its either the pump or the tank sock is glogged. To find out which one, take the line off the pump coming from the tank, add a hose and put it in a gas can. try to start, if you get gas out of the line going to the carb, then its the tank, if you dont, replace the pump.
Going back to the beginning, if fuel comes out of the line from the pump to the carb, then something is stuck or clogged in the carb.

 

I apologize for lateness of my reply, I have been on business for the past week and haven't had much time to look at the car since. But this morning I took a look at and found that when I try to turn it over no fuel is getting to the carb. Even when placing suction to the hose nothing comes up. I'll try to post picture tonight once when I get home. Thank you for all the help.