Arrowstorm

I've developed a problem recently when starting my 72 Vista Cruiser. In the mornings, or when I first start it up for the day, it takes a while to get started. At first, I suspected that it's because it wasn't getting fuel and maybe there was something in the carb blocking the fuel line.

Here are the symptoms:

When I first start the car, it turns over, but won't fire. It takes a minute or two of turning and then I can hear it start to fire until finally, it starts up and runs like a champ. At this point, I could turn the engine off completely, and turn the key and it will start right up. I noticed a while back that in my clear fuel filter, there wasn't any fuel, and I got my gf to start the car so I could see what that was doing and as soon as the engine turns, I can see fuel gushing into the filter.

My brolaw says that filter should always be full and the fuel is "leaking down" out of the carb somehow; probably due to an air leak.

Where could this be? The hoses are clamped good and tight from the carb to the filter and then from the filter to the pump.

He suggested a check valve in the line, maybe would help, but if there's an air leak, how do I got about finding it?

Any help would be appreciated.

Thanks,
Buz

oldcutlass

Next time before you start it for the first time, remove the air cleaner. With engine not running, look down into the carb and operate the throttle linkage by hand and see if there is 2 solid streams of fuel spraying in there. Looking at the fuel filter is not a gauge of fuel flow into the engine.

Also check your oil to see if it smells heavily of gas.

joe_padavano

^^^This!

The carb float bowl holds enough gas for the car to start and run for a minute or more without the fuel pump even working. If you don't see the accelerator pump streams, that means that the float bowl is empty. On my 62, the fuel will evaporate out of the float bowl if the car sits more than a week or two, thanks to the more volatile ethanol in gas today. It is nearly impossible for the fuel to crawl up the side of the float bowl and run backwards through the needle and seat once the bowl is filled. Just look at the inside of the carb.

It is also very unlikely (but not impossible) for fuel to leak out the bottom of the carb. Some carbs are less prone to this than others. The well publicized Qjet bowl plug problem really only applies to the 1966-67 carbs with the sheet metal plugs. Later Qjets with the spun-in aluminum plugs are not prone to leaking.

It is more likely that your choke is not adjusted properly. Also verify fuel pump performance.

Arrowstorm

I should have specified that the carb is an Edelbrock 1406 4bbl carb.

When I get home, I will inspect the carb more closely and see what's going on there.

That's what I thought was happening at first; that the fuel was evaporating out of the bowl, but this happens too frequently. I really only drive the car on the weekends, but if I drive it on friday night, it will still have that trouble starting on saturday morning.

I'll inspect the carb and see if the throttle delivers fuel right off the bat when I get home.

What if it doesn't? What's next? I suspect that it won't, because if it did, I'd hear the car starting to fire a lot sooner, wouldn't I?

joe_padavano

It could still be the choke or a non-carb problem. I'll note that my 62 also has an E-brock carb, with the evaporation problem after a week or so. If the fuel pump is weak, it may not be filling the float bowls all the way, leading to rapid depletion by evaporation.

oldcutlass

If there is no fuel squirting then I would then pop the top cover off the carb and see if there is fuel in there, if there is then you have a defective accelerator pump. If there is not then its time to look at other causes.

Tedd Thompson

My car suffers from this problem also(4gc) carb. My thoughts are that the fuel pump might be leaking back because of a bad check valve in conjunction with the bleed down problem through evaporation of alcohol based fuels. It would take quite a few revolutions to fill the lines and the carb enough to start the engine. I'm no carburetor guy but it is defiantly a shortage of fuel and it only manifests it's self after a period of 24 hours or more, what else could cause this? ... Tedd

Arrowstorm

Alright. So, I took off the aircleaner and looked down into the carb and I get NO streams of gas when I work the throttle. I know that I should see a little squirt; I've seen that before. But right now, there's nothing.

So, I unhooked the fuel line from the carb and there's no fuel at all in the line either. Not in the filter, nowhere in the line.

I took off the top of the carb and there is only a tiny amount of gas in both of the bowls; one left and right. I know there should be more gas in there as well, because I've had to adjust these floats before.

So where's all this gas going?! I also feel the need to point out that I don't use ethanol gas in the car. I run straight high octane gasoline about 90% of the time because I heard ethanol can really do quite a number on many key parts of an older car.

I should also point out that the mechanical fuel pump is also relatively new; not more than a year old, if that.

I can say that this is a new problem. When I've looked under the hood in months passed, I have noticed fuel inside the filter. But, to be honest, this problem was occurring (though not as bad; didn't take THIS long to start) before I recently bought a new fuel filter; as I thought that could be the problem. When I replaced the fuel filter (not even a month ago), the old filter would be full of gas, but this one isn't. I did notice that when I took the old one off, there was ZERO fuel in the line from the filter to the carb.

Any more help would be greatly appreciated!

Thanks,

Buz

oldcutlass

If you look at the carb, you'll notice that there is no way for the gas to go back into the fuel line. Take the carb off and set it on something that will support it so its level. Fill the bowl and place some paper towels under the carb, monitor to see where the fuel leaks.

You can disconnect the coil wire and hook up a vacuum/fuel pressure gauge and check your fuel pressure for piece of mind. Does your oil smell like fuel?

classicmuscle442

Maybe the old filter had a check valve?

Arrowstorm

Roger that on the carb. I'll pull it tonite and see what's up.

Negative on the oil smelling like gas. Not at all. It's fresh oil, too, so I'd probably detect any fuel at all. My uncle had a 4bbl Holley that dumped fuel into the chevy 350 that pushes his Malibu boat. I've smelled gas in oil before, thanks to that ordeal.

joe_padavano

Check fuel pump output. The easiest way is with the engine running. You can fill the carb float bowls using a syringe or similar tool through the vent tubes. Disconnect the fuel pump outlet line and run a hose from the outlet of the pump into a clean container. Start the engine and run for 15 sec. You should see a minimum of 1/2 pint of fuel pumped into the container. If output is less than that, the problem could be the pump, or it could be a clogged inlet sock in the tank, or it could be a cracked hose somewhere between the tank and the pump. In particular, check the hose from the tank sending unit to the hard line on the frame. Any cracks in the hose let in air, and once the pump starts sucking air, it won't be pumping fuel.

The more I think about it, the more I'd look at the hose first.

Arrowstorm

Well, the old filter did come with the new carb 2 years ago.

But like I said, it was giving me the hard start issue before I changed it. That's why I changed it out.

I have also noticed a little corrosion around the base of the carb..... The vacuum port rubber stoppers are a bit corroded and starting to split and the linkage and around the base of the carb just appears.... corroded a little. Maybe that's my imagination, but I don't remember it looking like that last time I pulled the carb.

Arrowstorm

Well, so what you're saying is that there should be fuel in the line going all thew way up to the carb and that it's somehow "leaking down"?

oldcutlass

I forgot to add check the float adjustment.

joe_padavano

Or not filling sufficiently in the first place. The fuel pump has one-way valves on both the inlet and outlet ports. If the valves are bad or have dirt holding them open, it will leak back. This is unrelated to the carb - it's a pump issue. Also, no check valve is perfect - there will always be some small amount of leakage.

Alternately, if the pump is sucking air due to a cracked hose on the suction side, you'll get some fuel and some air in the line, causing problems. Again, check the suction side hoses first, then pump output.

You can verify it isn't a carb problem by manually filling the float bowls through the vents. I do this on my 62 after it's sat for a week or so to avoid excessively cranking the starter until fuel flows. If the car starts and runs normally, the carb is fine.

Arrowstorm

Well I surely thank you guys for your input. It's storming here now, so I can't get under there to look. I will do that tomorrow and see what's up and report back on what I find.

Thanks!

oldcutlass

The carb should hold fuel in the bowl for a few days. I agree it can be a pump issue but can also be a float issue. If the float is set too low it will never fill the bowl up to the proper level. Edelbrock carbs are not prone to leaking as there are no gaskets below the fuel level.

joe_padavano

It was running better before the pump change. It is unlikely to be the floats. Keep in mind that a heavy float (leaking or fuel-impregnated) would keep the needle valve open longer, raising the fuel level in the bowl. The most likely problem is the pump or the suction side of the fuel system.

oldcutlass

I meant if the float was set so as the fuel level is too low. A sinking float is set right, just does not raise up to shut the fuel off.

MDchanic

Just read through this.

What Joe said: Check the hose between your tank and fuel line, or possibly rust pinholes in a steel fuel line.

Also, your new fuel pump could be crap, but I vote for the hoses.

- Eric

1BOSS83

Buz,

Couple things:

-You said you are not getting streams of fuel when you engage the throttle? If you are out for a drive and stomp on it, what happens?

- If the hose from the filter to the carb inlet is dry; what is going on in the hose from the fuel pump to the entrance of the filter? Is there fuel in there?

-What kind of fuel filter is it? I had a Mr Gasket fail on me recently.

-You could take a piece of hose directly from the fuel pump to the fuel inlet on the carb and check for streams. This can rule out of the filter at the very least.

nsnarsk65cutlass

The edelbrock or carter afb i think it's known as has 2 floats and if the accelerator side needle is sticking shut the accelerator pump has no fuel to draw from........

joe_padavano

I'm lazy, so when I troubleshoot, I'll check the most likely and/or easiest to check items first. It is EXTREMELY difficult for the float and needle to stick closed, at least in a carb like an AFB or Qjet. Gravity and pressure are working to open it. Can there be a clog due to dried out gasoline? Sure, but if the car has run within the last few days, this is almost impossible to happen that fast. Float and needle problems are almost always stuck OPEN problems, due to a bad float or debris in the needle/seat.

Given that the OP has already seen that there is little or no fuel in the output line from the pump, that suggests that the carb is not the problem (or, at least not the primary cause). Prudent troubleshooting would start at the pump and suction lines. Since it's easier (and cheaper) to inspect the rubber hoses before replacing a pump, that's what I'd do first.

MDchanic

Also note that sometimes when the hoses are quite porous, they will have an extremely thin coating of gasoline while the engine is running.

- Eric

Arrowstorm

I was getting no streams only as a check without the engine running. It has not been started since Sunday morning. After I get the car started (and it WILL start, it just takes a minute or two), it's fine. I could shut it off immediately after it finally fires and is turning without the starter engaged and when I turn the key again, it will immediately fire.

When I get it out on the road, it might stumble just a tad for the first few minutes if I gun it (it always has), but after that, it wants to fly. I could stomp on the petal and it will accelerate just fine.

I didn't check the line below the filter. The filter was bone dry, so I figured the line below it was as well.

The fuel pump was from Autozone, so it is either an AC Delco or a Duralast. If AC Delco is too expensive on something, I usually go with Duralast. I can't remember, but if they DO have AC Delco and it's not outrageously pricey, I will get the delco.

The fuel filter was definitely one I got from Autozone (off the shelf) and it is about a month old.

One more thing: choke is 100% disengaged with the butterfly wide open at all times. This occurs during warm and cold weather (we experience fluctuations of 80 degree days to 30 degrees the next and back up to 70 a couple days later).

Buz

joe_padavano

So you want to again spend money to replace a part that you may not need? Must be nice to have too much money and time. I'm cheap. I'd check the suction hoses first.

Arrowstorm

Lol. Oh lord, no! All my extra dough goes to this car anyway. I'll be checking those hoses before I do anything else at all, that's for sure.

I was just talking about when I need parts for a GM car in general.

Arrowstorm

I hope I'm not jumping the gun and speaking too soon on this, but I think I solved my problem and I feel like a doofus.. Yesterday when I got home, I decided to recheck my lines. I jacked the car up, put the stand under it, spread out some cardboard and prepared to get underneath when I decided to start from the carb first before I got under the car.

I double checked my fuel line at the carb and then at the filter. I noticed that I could twist the line at both ends of the filter; but not pull it off, so I tightened the clamp. Now.... I know I sound like an idiot, but I can't recall why I wouldn't have tightened the clamps down as tightly as possible, but I also can't for sure recall that I didn't. Maybe I was just lazy that day.

I also rechecked the fuel line at the pump and found that it, too, could use some clamping down.

So after I did that, I decided to go ahead and see what starting the engine would do and after a SECOND or a second and a half, I went ahead and looked at what was in the fuel filter and noticed that it was FULL of fuel already.

Last week, when I got my gf to start the car as I observed the filter, she was turning the key and as the engine was turning for about 5 seconds, I could see fuel "gushing" into the filter but not quite filling it up.

Now, yesterday, after only a second or so of turning over, the filter was full. So I went over to the carb and worked the throttle and looked down into the throat and could see fuel squirting from the jet.

Turned the key again and BAM. Started right up.

I feel stupid. But it still makes me wonder why I had starting troubles in the first place before I bought the new filter. That old filter was maybe 2 years old, but the starting problems with that filter didn't take AS long as this new one.

Do in-line Duralast filters get clogged up enough in 2 years of light driving to give a slight delay in starting a car once a week?

Oh well. I looked under the hood this morning and there was still fuel in that filter; at the same level as yesterday. Before I did those adjustments, it would have been empty. My brolaw says that the clamps might have been on there, but not tight enough and that definitely would have let air in the lines over time.

Hope this helps someone else out, and more importantly, I hope I'm not speaking to soon!!!

Buz

MDchanic

Is the filter between the steel line from the tank and the fuel pump, or between the fuel pump and the carburetor?

If it's between the pump and the carburetor, then the clamps were not your problem - if they had been, then gasoline would have been squirting all over your engine compartment.

If it's between the tank line and the pump, that could have been it.

Not a bad idea to take a good look at the hoses between the tank and the car, too, though.

- Eric

Arrowstorm

No, the filter is between the carb and pump.

I'll take your advice and go ahead and inspect the lines from the tank as well, though.

Buz