I just replaced the fuel pump on my '79 C3 350 L82. I was idleing the car one day with the old pump (looked like replacement also) one day and it just stopped. One of the first things I do is check gas at carbeurator. Not a drop. I figure the fuel pump is surely to blame and replace it. After a few cranks the engine starts. I let it cool a little and recheck before putting tools away. It starts fine. Great. I clean up my mess and put tools away leaving hood open to cool completely for a few hours. In four hours I come back to start the engine one last time before putting it away. It tried once or twice to catch but wouldn't start. Removed gas line at carb. Dry. Go back down below to outlet on pump and just loosen bolt about two or three turns and have girlfriend turn motor. Pressure looks good there. With each revolution of the motor it's shooting what seems to be a pretty forceful stream through the loosend threads and line flange. It's been a while since I dealt with a fuel problem, but I just don't understand why I'm not getting a drop (it's dry) of fuel at the carb end of that line.
I'm stumped I guess for now. Sure would appreaciate if someone maybe with similar experience would please direct me to do something or go somewhere or something. Thanks.

-Jack

 

Hey Jack,
I'll give it a shot, If you have fuel at the carb side of the pump but no fuel at the end of the line where it connects to the carb, (crank test this also with the line disconected from the carb) The line can sometimes get kinked when changing the pump. Who ever changed the previous pump may have inadvertantly kinked the line and when you changed it you may have unknowingly increased the kink to the point where the line is now blocked off. You may be able to get "some" fuel through the kink to start the engine or get it to "stumble" but not catch and run. Check the line for any kinks, if none found, remove the line and blow through it to make sure there are no obstructions in the line. If the line is kinked or clogged, remove the clog or replace the kinked line. I've taken my best shot on the line issue. If you get fuel at the carb end, that's another issue I may be able to help with. Good luck and let us know of the outcome.
Dave

 

Hey Dave,
Thanks for replying. I've followed the fuel line down to fuel pump and it does not appear kinked at all. I'll try blowing through the line. However, when I installed the new pump it did run fine. I turned the engine off for a few minutes and run it again. Run fine. After letting it cool for 3-4 hours is when it wouldn't start. That's when I took the line off at the carb and it was dry except for a few drops that backed out of carb. It does seem they're must be some kind of blockage between fuel pump and carb. Seems strange that it run fine twice and then didn't after I put my tools away and thought I'd done good for my C3. LOL. Can't cry...yet. I'll take your advice on making sure that line is clear. Thanks alot.

-Jack

 

Hey Jack,
The carb could have had enough gas in it to get the car to run a short time, even twice, especially if you just let it idle. The last time you tried to start it, the carb bowl was probably empty so no more gas to make it run.
Keep me informed, I'll try to help you along.
Dave

 

Hey Jack,
If your fuel line is O. K.,.........
I don't know what your mech background is, so I'm going to make another shot and don't mean to insult you. When you installed the fuel pump, you should be able to feel the pump actuate upon instalation. If the pump went in real easy, you may have missed the possitioning of the push rod that actuates the pump operation. Tryin' to help, I know how it is when the baby is sick.[]
Dave

 

As strange as this sounds, it could be a bad new pump. Have you tried checking the pressure?

 

How about the filter inline and the one in the carb where the line comes in? Or even stuck floats in the bowls. I had an old '70 c10 pickup and the same thing happend. left me on the side of the road. I checkd the pump, filter and feul line and all were fine couldn't figure it out for s&it. called my brother-in-law for a tow and the first thing he did was tap on the bowl with the handle of a screwdriver....tap,tap,tap...guess what...started right up. good luck brother.

 

Too true, so often we overlook the simplest of cures. I've been lookin' too hard!!!