Fuel Filter Empty

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Paladin06

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On to my next item to fix on my 1972 Plymouth Duster 340. I've noted that after the car sets for awhile, the fuel filter is completely empty. There are no obvious fuel leaks visible.

Where should I start.

Thanks in advance.

Greg
 
Wish I could help . My '72 340 is the same way. Takes quite a bit of cranking to start.
Yote
 
Carter sells a muscle car series, for around $30.
 
Does your pump have round body with screws or is it crimped? There are 2-3 rubber flap (outlet valves) pressed in there. One may not be seating. I have found the little rubber pucks dislodged and sitting at the base of the pump.
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M6270 was the 'competition' pump and had a cut off pressure of 7.5 psi. In other words, needs a regulator.
M6902 was the 'Super Street' pump and had a cut off pressure of 6 psi. That's was the better choice for 99% of users.
Can't speak to the recent reissue of these pumps personally, but have read here of pressure regulation issues.
If replacing, I'd suggest a stock replacement, or Holley 110 mechanical if there is uncertainty about the cut-off (aka maximum pressure).
 
My fuel pump was new less than 3 years ago and problems stated above have been with me since and car was not operable before that.
Yote
 
Is it vapor? When i ran a Holley double pumper it was set up with two transparent fuel filters immediately before the carb inlets. The filters normally looked only half full--until I added an aluminum "cool can" and added ice at the drag strip--the filters thereafter would be completely full (as long as the ice held out, that is). I was using a Holley electric fuel pump with pressure regulator at the time (no mechanical pump).

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OK, I replaced the fuel pump and BINGO.. Another thing noted is the fact that before the pump change with the car running the filter was never completely full. Now it is completely full. Also the car has set over night and the filter is still full this morning.

Thanks @mopar head and all the rest!
 
Ok spoke to soon. Took the car to the about 6 miles round. Car started to run funny. Got home popped the hood and the fuel filter was damn near empty. No fuel leaks but an oil leak around the pump. WTF. Man I can not get a break. Guess I’ll need a new pump, again.
 
If the fuel pump loses pressure after shutoff and the Float seat in the carb loses the vacuum while setting, the gas flows down hill
 
While your at it, maybe verify their is no fuel restriction or vent problems.
Hopefully it`s just a bum pump and you can replace and drive happily ever after
 
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While you at it, maybe verify their is no fuel restriction or vent problems.
Hopefully it`s just a bum pump and you can replace and drive happily ever after
The new pump was working just fine when I drove the car around the block after I replaced it. The filter was staying full of fuel over night. Today oil leak at the pump and zero fuel in the filter.
 
Does your pump have round body with screws or is it crimped? There are 2-3 rubber flap (outlet valves) pressed in there. One may not be seating. I have found the little rubber pucks dislodged and sitting at the base of the pump.
View attachment 1715180215View attachment 1715180216
I have the same hard starting problem with my 65 Barracuda. Are you implying that the stock type fuel pump can be repaired or Rebuilt? I'm tired of trying different fuel pumps and would like to see the problem and then know that it's fixed.
 
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?
 
If it's the non crimped round one with the Allen bolts holding the upper and lower together, yes, it is repairable. Crimp is a throw away. What carb is this? Carter won't lose fuel unless it's boiling it out, very common without a phenolic/wood/plastic spacer. Neither will a holley but those bowls are more insulated from the intake heat. Both (all) carbs use engine vacuum to pull fuel out the bowls. None have a built in drain 'cept the TQ with bad jet O-rings. I finally went to a carter electric in my 65 cartered 340 as the bowls would be dry every morning. 5 seconds of pumping and the bowls would be full and the car would start under 1 revolution. I'm sure it was heat soak caused as I never had driveability issues.
 
I have a Carter AFB on an aluminum manifold. Should I try an insulating carb spacer?
 
Absolutely! Carter on an AL intake is like a pot of water on a grill. You can make one out of MDF or marine plywood or just buy a plastic one. Even nylon washers under the mounting bolts will block heat transfer.
 
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