OK, I have a 74 duster with 318 and 727 tans. First time I had a problem it seemed like I was out of gas when the engine would not fire and the fuel filter appeared to be empty, the fuel guage read 1/4 tank and engine was cool. Filled tank, about 10 gallons, and it started and ran fine. This time fuel gauge was reading 1/2 tank and the car stalled and would not refire, again the fuel filter was empty and would not fill up after cranking engine. filled gas tank, took 7 gallons and it fired an ran fine. Has anyone else run ito this problem or heard of it before? I do not want to drop the tank if I don't have to or replace the fuel pump if thats not the problem.
Out of gas or not?
- Thread starter Duster_71
- Start date
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This may seem silly, but when you removed the filler cap did you hear a whoosh of air?
67Dart273
Well-Known Member
Not silly and probably right on the money. To the OP. READ the shop manual sections on fuel (tanks) and emissions. The vent system is explained. You may have something modified, leaving what was the vent system plugged, or the cap may be corroded up. These caps ARE NOT intended for "normal venting," they are instead what is known as a "pressure / vaccum" cap, which means that spring release valves vent if the vacuum or positive pressure in the tank gets so high
You can download a SEVENTY THREE manual here for free, there MIGHT BE some differences in the 74 system.
http://www.forabodiesonly.com/mopar/showthread.php?p=1970088617
DOES IT APPEAR that the factory engine bay "carbon canister" is all properly hooked up?
Look for a 1/4 steel line coming from the tank area up front
No, I do not hear a whoosh, is that good or bad?
If the car sat for any amount of time before you removed the cap it may have lessened some.
Typically if you hear a whoosh of air when pulling the cap, not good. What happens is, there is vacuum created in the tank and at some point the fuel pump can't overcome it and pull fuel to the engine.
I do not know if the manual will help me as there are no emissions equipment remaining on my car with the exception of the vapor canister; which is hooked to the tank but that is it. As stated earlier I'm running a 1405 eddy carb, "no emissions". As stated to another poster I do not get a whoosh when I remove the gas cap.
Well no whoosh ever (i.e., sit for long time or drive for miles and stop and fill up), does this point to something else?
67Dart273
Well-Known Member
No whoosh would indicate that you do not have a vent problem.
These are simple systems, but you do have to get your hands dirt. There are only "so many things.
1....Problems with the pickup. Is the tank dented from a wreck or dragging on something? The sender could be damaged
The sender pickup screen could be clogged with gum, rust, etc. Only way to find out is to find a gasket for it, drain the tank and pull it off
2....Don't mess with them REPLACE both suction side hoses. There's one from the tank sender to the fuel tube, and another up front from the fuel tube to the pump
3....TEST the pump. Read the manual. There's procedures in there. You need a pressure / vaccum gauge, which you should have, and which you can buy at any parts store for under 20 bucks. You'll need some sort of container to measure flow
4....Might be pinholes in the fuel tube, small enough to not leak sitting, but to let air in. The tube could also be clogged with rust. Blow it out with air.
5...Could even be problems with the carb. Get some fittings and "rig" your pressure / vacuum gauge to monitor running fuel pressure to the carb. If you see a min. of say, 3 psi and no less when the problem occurs, then it's not fuel supply.
These are simple systems, but you do have to get your hands dirt. There are only "so many things.
1....Problems with the pickup. Is the tank dented from a wreck or dragging on something? The sender could be damaged
The sender pickup screen could be clogged with gum, rust, etc. Only way to find out is to find a gasket for it, drain the tank and pull it off
2....Don't mess with them REPLACE both suction side hoses. There's one from the tank sender to the fuel tube, and another up front from the fuel tube to the pump
3....TEST the pump. Read the manual. There's procedures in there. You need a pressure / vaccum gauge, which you should have, and which you can buy at any parts store for under 20 bucks. You'll need some sort of container to measure flow
4....Might be pinholes in the fuel tube, small enough to not leak sitting, but to let air in. The tube could also be clogged with rust. Blow it out with air.
5...Could even be problems with the carb. Get some fittings and "rig" your pressure / vacuum gauge to monitor running fuel pressure to the carb. If you see a min. of say, 3 psi and no less when the problem occurs, then it's not fuel supply.
Well, there are some simple things to check next.
First I would look at the rubber sections of fuel line, this new fuel crappolla we're forced to use can raise cain with the old line. It could be collapsing on the inside.
I don't know how old your rubber lines are, but it might be worth changing them. Be sure and get the newer line that's resistant to ethanol.
Another possibility is the pump itself failing.
You could get about a three foot piece of fuel line and run it from a gas can directly to the pump and see how it picks up the fuel.
Another possibility is the sock on the sending unit plugs up, and when you add gas it stirs it up enough to clear it some.
Whatever you do, start with the simple stuff first and work your way through it. Without knowing the condition of your car, it's hard to say for sure. Could be just a small hole in the fuel line somewhere so it starts sucking air.
First I would look at the rubber sections of fuel line, this new fuel crappolla we're forced to use can raise cain with the old line. It could be collapsing on the inside.
I don't know how old your rubber lines are, but it might be worth changing them. Be sure and get the newer line that's resistant to ethanol.
Another possibility is the pump itself failing.
You could get about a three foot piece of fuel line and run it from a gas can directly to the pump and see how it picks up the fuel.
Another possibility is the sock on the sending unit plugs up, and when you add gas it stirs it up enough to clear it some.
Whatever you do, start with the simple stuff first and work your way through it. Without knowing the condition of your car, it's hard to say for sure. Could be just a small hole in the fuel line somewhere so it starts sucking air.
GEO
Sarcasm Inc.
As Bad Sport said I would check the sock on the fuel pickup tube
"I don't know how old your rubber lines are, but it might be worth changing them. Be sure and get the newer line that's resistant to ethanol." I replaced them this past spring.
I wouldn't think so but what about Vapor Locking, could that be a possibility? At some point I may drop the tank and check the P/U. I haven't noticed any fine sediment in the fuel filter.
Dartswinger70
Well-Known Member
Just my .02 on vapor lock, as I have experienced it. My car had hedman headers and would shut down when cruising. I would wait ten minutes and start up and go. I too though that it was out of gas, however after you put 30 or 40 dollars worth of gas in on the same day and you don't drive very far,that gets ruled out quick. Anyway my fuel line up front near the fuel pump was away from the frame rail a little bit. I pulled it away from the header collector maybe 1 1/4 inch and wired it fast with mechanics wire to the frame and the car never shut down again.
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