Fuel Filter Empty

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mopar head said:
Oil leak is on you. Make sure your oil does not smell like gas. Re seal, run/drive shut down, remove gas cap and notice if it makes a woosh vacume sound.

If you have over a 1/4 tank of gas, jack up the back of the car a little and remove the inlet line to the pump into a tub, with gas cap off, gas should flow. If not, may be time to pull the sender and inspect.
As post 15 states, could be the culprit too. What carb. are you running?
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Humm oil leaks not from the pump but the dip stick sleeve.
 
Paladin06 said:
Humm oil leaks not from the pump but the dip stick sleeve.
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What do you mean the dipstick sleeve? at the base , the top. if your oil level went up; to the point of overflow you are pumping gas into the block "Do not start it" check the oil for gas before you do anything!
 
Check every rubber jumper hose on the suction side all the way back to the tank, especially the one at the sender. It is higher than the tank so will not leak, but the pump will suck air there if the hose is old or if someone installed gearclamps there; one on each side, instead of the oem bandclamps.
If you have to use gearclamps, install the correct really small ones and use two per side with screws rotated 180* from eachother.
 
Fuel filter empty when it sits. What problem does it actually CAUSE? Is it hard to start?
 
AJ/FormS said:
Check every rubber jumper hose on the suction side all the way back to the tank, especially the one at the sender. It is higher than the tank so will not leak, but the pump will suck air there if the hose is old or if someone installed gearclamps there; one on each side, instead of the oem bandclamps.
If you have to use gearclamps, install the correct really small ones and use two per side with screws rotated 180* from eachother.
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I did notice bubbles yesterday so I’ll check all rubber hoses today.
 
There doesn't have to be any fuel in the filter at start. As long as the bowl(s) have fuel, that's all that's needed.
Start by checking whether there is fuel in the accelerator pump (should shoot some out with any throttle movement) and check the fuel level.
After that, choke settings.
But if there is little or no fuel in the bowls or accel pump, then that's what needs to be solved.
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Remember the fuel we call "gasoline" starts to vaporize around 100 *F
So if any of it gots near 100 F while under suction (on the way to the pump) a small portion will vaporize. After the pump its under slight pressure, so it won't start to vaporize until a slightly higher temperature. Engine off, fuel is not flowing, everything is getting heat soaked and some vaporization is to be expected.

The 'heavy' components of street fuels don't vaporize until well over 300 *F, and for that reason aren't as easy to light off. The main difference in winter and summer fuels is the components that make up the 'light' end. Winter fuels vaporize easier and can be a b*tch when used in hot conditions.
 
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Slightly O/T but a couple graphics showing vaporization points of street fuels from around the begining of reformulated gasoline (RFG) going to ethanol blends.
file.png

In these particular fuels, vaporization begins just around 105 to 110*F.
More important, notice how much of the fuel with 8% ethanol was evaporated at 150*F. 30%
and compare that with the 2007 E0 at 150 F, which had just 8% evaporated.
(Just going to E0 fuels does not solve the problem entirely. Other components now added to the blends, especially in the winter, also change the shape of the curve. There are different blends throughout the US to meet various regs and climates. Some states even have 'drivability' requirements. Everyone should be getting summer fuels now.)
 
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AJ/FormS said:
Check every rubber jumper hose on the suction side all the way back to the tank, especially the one at the sender. It is higher than the tank so will not leak, but the pump will suck air there if the hose is old or if someone installed gearclamps there; one on each side, instead of the oem bandclamps.
If you have to use gearclamps, install the correct really small ones and use two per side with screws rotated 180* from eachother.
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I did find several location where I could twist the hose with my fingers. If I can twist it I know air was getting in.
 
OK thought I had the problem solved. Everything seems fine idling in the driveway. Since it's below 100 today I took the car for a drive. First thing I noticed is the car idles at almost 1900rpm all by itself after it gets warm. Normal idle is about 700rpm.

Second when I got back to the house I could see large air bubbles in the fuel filter and the filter is no longer full like it is idling in the driveway. Perhaps the new pump is bad. I did not replace it yet. Trying to avoid that but I have ANOTHER new one sitting on the shelf.

Your thoughts, ideas welcome as always.
 
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You have more than 1 problem

A) The high idle points to a choke issue,like stuck on the fast-idle cam;
or possibly a vacuum leak, like a stuck-open PCV or other
B) The pocket in the fuel filter I have seen many times. Sometimes it means nothing.
There's really only three ways for that pocket to get there, and it may not be air at all.
1) the pump sucked it up; that would be air
2) it's boiling in the line; that would be gas in vapor form.
3) the fuel flashed into vapor after it came out of the pump


As to #1), Have you done the fuel pump output test yet. This will take care of proving #1
As to #2),This you can address by insulating the line and divorcing it from the engine
As to #3, this only happens if the pressure in the line to the carb drops and the fuel is hot.Like if the float valve is not sealing, or you have a fuel leak on the pressure side.
Or if the fuel is forced through a smaller hole, or over a pointy thing,
or if the fuel pump has to suck really hard on the supply line; then it will flash on the suction side into bubbles, and come thru the pump that way, and accumulate in the filter, or be forced along into the floatbowl. This could be due to a faulty tank-vent or a restricted supply line, or a kinked hose.
Usually on the pressure side, the fuel vapor will re-constitute into liquid.

But I just gotta tell you man, the pump tests are a big deal. It will tell you if the pump is making pressure, making vacuum,delivering liquid fuel or sucking air, or keeping it's prime. There is no way I would start throwing pumps at it until I did the tests. And if the tests say the pump is good, I wouldn't worry about the filter not being full. If you want it to be full; install it in a vertical part of the line , below the bottom of the float bowl. Then if it doesn't stay full, I would question it.

C) your engine may be running hotter than it should be. This may be a timing issue, a carburetion issue, a mechanical issue, or a cooling system issue.
 
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AJ/FormS said:
You have more than 1 problem

A) The high idle points to a choke issue,like stuck on the fast-idle cam;
or possibly a vacuum leak, like a stuck-open PCV or other
B) The pocket in the fuel filter I have seen many times. Sometimes it means nothing.
There's really only three ways for that pocket to get there, and it may not be air at all.
1) the pump sucked it up; that would be air
2) it's boiling in the line; that would be gas in vapor form.
3) the fuel flashed into vapor after it came out of the pump


As to #1), Have you done the fuel pump output test yet. This will take care of proving #1
As to #2),This you can address by insulating the line and divorcing it from the engine
As to #3, this only happens if the pressure in the line to the carb drops and the fuel is hot.Like if the float valve is not sealing, or you have a fuel leak on the pressure side.
Or if the fuel is forced through a smaller hole, or over a pointy thing,
or if the fuel pump has to suck really hard on the supply line; then it will flash on the suction side into bubbles, and come thru the pump that way, and accumulate in the filter, or be forced along into the floatbowl. This could be due to a faulty tank-vent or a restricted supply line, or a kinked hose.
Usually on the pressure side, the fuel vapor will re-constitute into liquid.

But I just gotta tell you man, the pump tests are a big deal. It will tell you if the pump is making pressure, making vacuum,delivering liquid fuel or sucking air, or keeping it's prime. There is no way I would start throwing pumps at it until I did the tests. And if the tests say the pump is good, I wouldn't worry about the filter not being full. If you want it to be full; install it in a vertical part of the line , below the bottom of the float bowl. Then if it doesn't stay full, I would question it.

C) your engine may be running hotter than it should be. This may be a timing issue, a carburetion issue, a mechanical issue, or a cooling system issue.
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Man all good points. Perhaps I’ll start with the easiest, I did replace the PCV valve for no real reason. Stupid me.
 
Paladin06 said:
Man all good points. Perhaps I’ll start with the easiest, I did replace the PCV valve for no real reason. Stupid me.
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You got to be kidding me. I just went to remove the PCV valve and it came a part in two pieces. After removing the piece stuck in the grommet it is stuck. No rattle at all.
 
AJ/FormS said:
You have more than 1 problem

A) The high idle points to a choke issue,like stuck on the fast-idle cam;
or possibly a vacuum leak, like a stuck-open PCV or other
B) The pocket in the fuel filter I have seen many times. Sometimes it means nothing.
There's really only three ways for that pocket to get there, and it may not be air at all.
1) the pump sucked it up; that would be air
2) it's boiling in the line; that would be gas in vapor form.
3) the fuel flashed into vapor after it came out of the pump


As to #1), Have you done the fuel pump output test yet. This will take care of proving #1
As to #2),This you can address by insulating the line and divorcing it from the engine
As to #3, this only happens if the pressure in the line to the carb drops and the fuel is hot.Like if the float valve is not sealing, or you have a fuel leak on the pressure side.
Or if the fuel is forced through a smaller hole, or over a pointy thing,
or if the fuel pump has to suck really hard on the supply line; then it will flash on the suction side into bubbles, and come thru the pump that way, and accumulate in the filter, or be forced along into the floatbowl. This could be due to a faulty tank-vent or a restricted supply line, or a kinked hose.
Usually on the pressure side, the fuel vapor will re-constitute into liquid.

But I just gotta tell you man, the pump tests are a big deal. It will tell you if the pump is making pressure, making vacuum,delivering liquid fuel or sucking air, or keeping it's prime. There is no way I would start throwing pumps at it until I did the tests. And if the tests say the pump is good, I wouldn't worry about the filter not being full. If you want it to be full; install it in a vertical part of the line , below the bottom of the float bowl. Then if it doesn't stay full, I would question it.

C) your engine may be running hotter than it should be. This may be a timing issue, a carburetion issue, a mechanical issue, or a cooling system issue.
Click to expand...

The PCV valve fixed the idle issue. The new fuel pump resolved the fuel issue. I also insulated all the metal fuel lines in the engine compartment and replaced all the pinch clamps. So she has good fuel, Good idle, temperature running about 190 all day long.

Thx so much again.
 
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