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-   -   Help needed with fuel issue (https://67-72chevytrucks.com/vboard/showthread.php?t=320915)

VA72C10 12-27-2008 09:57 PM

Help needed with fuel issue
 
UPDATE:
I pulled the line coming in to the fuel pump and the gas immediately poured out. Luckily had my gas can there to catch it all (good to plan ahead sometimes) It filled up the 2 gallons (figured I'd put it back in and make sure I knew how much I had)

I'm guessing if the fuel is flowing (and looked decently clear) that that narrows it down to the fuel pump? I plan on going to the parts store this afternoon to pick a new one up. If it could be something else feel free to let me know ;)



Original post
On my 69 shortbed I'm selling, I was going to drive it today to keep it running good for the next owner. It has always been hard to start, but ran like a top once started. Today, It will only start w/ gas added directly to the carb. It runs a few seconds until the gas runs out. It has one of the clear fuel filters on it (Has been on there for years from what I was told) I changed the filter today to see if that was an issue. No gas is coming through the filter at all. Obviously this is why it cuts off and won't start w/out adding gas to the carb. I know that there was/is bad gas in the tank from sitting. I have added a gallon of new gas but done nothing with the tank. I am guessing that the filter at the sender is clogged or that the fuel pump is bad. Anything to try before I pull the sending unit? Is there a way to check if it's the fuel pump? Would I be getting any gas pulled through the fuel pump even if it was bad w/ the engine running?

When it runs there is no smoke and it runs smooth and pretty strong for a stock engine. It ran just before I parked it a few weeks ago (but had to add gas to get it to start last time as well----only that time it continued to run once it started.)

If I do have to pull the sending unit, is there a way to move the stock bench forward enough to get to it w/out taking the bench all the way out?

Thanks for any help!

1968SWBBigBlock 12-27-2008 10:07 PM

Re: Help needed with fuel issue
 
I would double check and make sure you have fuel in the tank - sounds to me like you are out of gas.
You could also pull off the line between the pump and the tank and see if gas flows out (make sure to take off the gas cap)
Give it some time to keep flowing.
If you do not get any fuel out of the tank try running a line from a gas can to the fuel pump and start the motor and keep it running for a few seconds with fuel in the carb.
If it pulls fuel check before the pump - if not replace the pump

cdowns 12-27-2008 10:11 PM

Re: Help needed with fuel issue
 
disconect the line going to the pump and with very lo pressure and the gascap off blow air back into trank to unclog the fuel sock

VA72C10 12-27-2008 10:12 PM

Re: Help needed with fuel issue
 
Thanks for the fast response.

I was thinking of the gas can idea...just want to get someone to hold it so it doesn't tip while i'm testing things out. I just added a gallon and there was gas before (could hear it sloshing), plus the gauge shows about 1/2 tank. But i will add a couple more gallons first just to be sure it's being picked up.

VA72C10 12-27-2008 10:13 PM

Re: Help needed with fuel issue
 
Quote:

Originally Posted by cdowns (Post 3049761)
disconect the line going to the pump and with very lo pressure and the gascap off blow air back into trank to unclog the fuel sock

I will try that as well when I have that line loose. Thanks!

100%Chevy 12-27-2008 10:52 PM

Re: Help needed with fuel issue
 
Might be the fuel pump.As said,see if it will pull gas from a can.If not,check the inlet to the pump,it may be clogged with old gas(thick,black stuff,very gummy,sticky).Almost nothing will cut this stuff!If it is,then the fuel line all the way to the tank will be the same,including the sock and the pick-up tube.
I pulled the tank on my 68 today,because of this.I've already replaced the fuel pump.The tank was litterally full of garbage.About 10 pounds of it!The sock was black and solid!It fell apart as I pulled it off the tube.I put some chain in the tank and cleaned on it for about 3 hours,constantly rinsing it with water.Put in new sending unit and pick-up.
Mine has buddy seats and I had to take them out to remove the tank.
So,I hope it's your fuel pump or you may be in for it!
Mike.:chevy:

VA72C10 12-29-2008 01:43 PM

Re: Help needed with fuel issue
 
UPDATE:
I pulled the line coming in to the fuel pump and the gas immediately poured out. Luckily had my gas can there to catch it all (good to plan ahead sometimes) It filled up the 2 gallons (figured I'd put it back in and make sure I knew how much I had)

I'm guessing if the fuel is flowing (and looked decently clear) that that narrows it down to the fuel pump? I plan on going to the parts store this afternoon to pick a new one up. If it could be something else feel free to let me know ;)

VA72C10 12-29-2008 03:07 PM

Re: Help needed with fuel issue
 
ttt

Palf70Step 12-29-2008 03:11 PM

Re: Help needed with fuel issue
 
I would think the pump is the problem too.

71tahoe 12-29-2008 03:44 PM

Re: Help needed with fuel issue
 
You can check the pump the same way you did the tank. If you have a hose to the carb take loose and run it into the gas can. If you have the steel line, take it loose and attach fuel hose and run it to a can. When it cranks, fuel should pump into the gas can. Good flow below the pump and no gas to the carb means bad pump. If you get fuel to the carb, you may have a filter completely clogged or a bad carb.

VA72C10 12-29-2008 03:50 PM

Re: Help needed with fuel issue
 
I have one of those " fire hazard" clear fuel filters so I can see if the fuel is flowing between the fuel pump and carb...which it was when i last had the truck running, but isn't now.

cdowns 12-29-2008 03:56 PM

Re: Help needed with fuel issue
 
if its a quadrajet carb it does have a fuel filter in the carb body/where the gas line enters the carb the very large nut take that off to access the carb filter

70rs/ss 12-29-2008 04:12 PM

Re: Help needed with fuel issue
 
If no fuel is getting into the clear filter, the pump is shot, i like to replace mine every few years just to be sure I don't get stranted!! They are only $15 at the parts store, more if you have to have a perf version, but it is the best $$$ you'll spend and the truck will fire right up, I'll bet!


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