Carb not squirting fuel and fuel filter holds half fuel

[79trumpduck]

I have a 79 gmc c6000 with a 350 in it. The truck is not starting... it turns over but will not engage in starting. The carb is not squirting fuel and I checked the fuel filter and it’s only halfway full of fuel. I’m not sure if fuel is not coming out of tank or if there’s issues from the filter to the pump... or if there is another issue elsewhere. I’ve installed a new pump, and previously cleaned out tank and ran new lines. The truck ran great a week ago. Was parked a week now won’t start. I could also have some distributor issues due to I had to advance the plug wires to get to fire last time. Any advice would help... thank you in advance

 

[PrairieDrifter]

Fix the timing or plug wire routing, whatever you did, then try and give it a go. If it won't fire dump some fuel straight in the carb then see if it'll fire, if it does fire you know you have a fuel issue. Sometimes pumps take a while to prime so that could be an issue, but generally if there is fuel at a filter near the carb, the fuel pump is working, they don't ever "fill" the fuel filter full. If you can make sure your timing is good that would be a good thing, but at the least check for spark. You can also try priming the pump by shooting some compressed air into the gas tank, covering the inlet with a rag trying to hold air in, don't go crazy with the air.

Don't rule out the pump just cuz it's new, as I've gotten straight out of the box garbage pumps(oreillys lol), if you exhaust the other options pull the inlet line to the carb off and stick it into a bottle then crank the engine over for a few seconds and watch the line, should be a decent bit of fuel. Then lastly if all other options are working, carb work may be needed.

 

[potent rodent]

check your rubber fuel lines from pump to tank

 

[Ricko1966]

Prairie drifter has given u good advice, dump some fuel down the carb and see if it will start and prime. You may have a bad accelerator pump or plugged discharge nozzles, or a stuck needle and seat I've had all of these.Now just to throw a new piece into the equation, the fuel pump arm works off of a eccentric on the camshaft if that eccentric goes flat you can put 500 factory replacement pumps on but still not get fuel.See if it starts if you dump fuel in it.Fill the float bowl through the vent tube using a dish soap bottle full of gas. Does the pump shot come back? Pull the fuel line at the carb is the pump pumping. Let us know then we an dive deeper into this.

 

[79trumpduck]

I’ve replaced the line from the tank to the filter. And yes it does fire when I put fuel straight into the carb but of course it dies after a second or two. About a tank ago or so I replaced the fuel pump and hauled all day no problem. Sat for a week and went to fire up and here we are. I did however hear a sound a couple times that reminded me of a vacuum. Not sure where to start with that either. Also I think the carb is Rochester and I have researched that some to find out a lot of issues with are mostly an accelerator pump. How do I check for this, location, etc.?? I really appreciate everyone and the feedback. So grateful for you all. Thank you

 

[Ricko1966]

Accelerator pump won't keep it from running just hard to start and stumble or die on acceleration. As prairie drifter said pull the line at the carb put it in a bottle and crank see if gas pumps into the bottle.

 

[82sbshortbed]

Maybe tank sock is dirty and clogged. Put inlet hose in gas can and see if you can get it to run that way. If so your tank may be clogged.

 

[79trumpduck]

Bout to go try some of the things you guys have told me about. Thank you all and I will post when I get home