Fuel Filters

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74Dart_Girl

74Dart_Girl

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I have a 1974 dart with a slant 6 in it. Im going through the manuals and see that there is a possibility of there being 2 fuel filters.

I know there is the inline filter, is there the second one in the fuel pump at this age?
 
I do know there are two types of fuel pumps, one is a regular old pump and the other pump is of the California emmisions type. I'm no expert on fuel pumps, but make sure no fuel is leaking from them. In terms of filters from pump to carb, I like the metal canister filters. I never liked the idea of fuel running through plastic over a HOT intake manifold!
 
The first filter,more of a screen(often called the sock) is in the fuel tank attached to the pickup tube.As you have stated the other is the "can" filter located after the fuel pump and before the carb.
 
I used to run 2 filters....one before the pump, and one after....the first was to stop crud getting in the valves of the pump......the sock in the tank only stops house bricks.
 
cjh said:
I used to run 2 filters....one before the pump, and one after....the first was to stop crud getting in the valves of the pump......the sock in the tank only stops house bricks.
Click to expand...

Putting a fuel filter before the fuel pump restricts the fuel feed as it is gravity fed. It's best to put the filter after the pump, before the carb.

If the 'sock' in the tank on the fuel sending unit is in good shape, it will not let "house bricks" through.
 
74Dart_Girl said:
I have a 1974 dart with a slant 6 in it. Im going through the manuals and see that there is a possibility of there being 2 fuel filters.

I know there is the inline filter, is there the second one in the fuel pump at this age?
Click to expand...

No filters built into the fuel pumps if that is your question.


there is a "sock" on the pick-up tube on the fuel tank sending unit in the gas tank, and you should have a canister filter between the fuel pump and carb.
 
1970Dart198 said:
In terms of filters from pump to carb, I like the metal canister filters. I never liked the idea of fuel running through plastic over a HOT intake manifold!
Click to expand...


I like the see through plastic filters before the carb. If properly located, heat is not a problem. I once changed an engine thinking that there was something wrong, only to find out that my gas tank was empty.... :banghead:

For some reason, my fuel economy was worse than I thought and I ran out of gas. (gas gauge wasn't working at the time and I just calculated how far I could go by mileage). :hmph:

Heat is not an issue if you have the filter properly located and today's plastics can handle the underhood temperatures.
 
krazykuda said:
Putting a fuel filter before the fuel pump restricts the fuel feed as it is gravity fed. It's best to put the filter after the pump, before the carb.

If the 'sock' in the tank on the fuel sending unit is in good shape, it will not let "house bricks" through.
Click to expand...


The fuel pump isn't just gravity fed. It pulls/sucks the fuel so long is the line isn't collapsed or otherwise restricted and the tank is properly vented.
The pick up screen in the tank isn't any different from those found in todays in tank electric pump applications. When a tiny object has razor sharp edges, the filter elements will only slow it down.
Every foreign object found caught in those fuel injectors returned to the mfgr, when magnified, looked like tiny swords.
 
Please forgive my naiveness yet again, but how do I get to the sock filter?
Going off of what others have told me in my other post, I may need to change it. I want to be prepared to deal with it. :)
 
A lot of work to remove the fuel sender. I would test the flow first. Disconnect the fuel hose on the suction side of the fuel pump (metal tube from tank). Catch the flow in a bucket. If it pours out, your sock is not plugged, so no problem to fix. If if doesn't flow fast, put a rubber hose on it and blow back into the tank. That could free gunk and let you run for many years until you actually need to remove the sender.

The sock could be missing (common), but you could just install a fuel filter (carburetor type) on the suction side of the fuel pump to mitigate that.
 
krazykuda said:
Putting a fuel filter before the fuel pump restricts the fuel feed as it is gravity fed. It's best to put the filter after the pump, before the carb.

If the 'sock' in the tank on the fuel sending unit is in good shape, it will not let "house bricks" through.
Click to expand...

Your not up on aussie slang, eh?
House bricks is a slang term for large particles....particles that usually get filtered out in a proper filter.....the sock in the tank isn't a proper filter.

As for fuel filters restricting flow......try blowing through a new one......no restriction.
When a fuel filter is restricting flow, it's because it is ready to be changed out.
 
74Dart_Girl said:
Please forgive my naiveness yet again, but how do I get to the sock filter?
Going off of what others have told me in my other post, I may need to change it. I want to be prepared to deal with it. :)
Click to expand...


You have to remove the gas tank sending unit from the gas tank.

You will have to remove the fuel hose, then the ground clip (long metal strap), then the lock ring rotates and you can get the sending unit out. the "sock" is on the end of the sending unit.
 
cjh said:
As for fuel filters restricting flow......try blowing through a new one.....
Click to expand...

You're hired!!! :blob:

Can you come over and blow mine and see if it's ok??? LOL! 8-[
 
cjh said:
Your not up on aussie slang, eh?
House bricks is a slang term for large particles....particles that usually get filtered out in a proper filter.....the sock in the tank isn't a proper filter.

As for fuel filters restricting flow......try blowing through a new one......no restriction.
When a fuel filter is restricting flow, it's because it is ready to be changed out.
Click to expand...


Ok, seriously...


A new filter may not have much restriction, but when they get dirty, they will.

I would not want to keep removing the filter every few thousand miles to blow through it.... That would suck... I mean blow... ..um, you know what I mean....
 
If you try to clear the in tank filter with compressed air via the fuel line, be sure to open the filler door. Otherwise you would balloon and maybe rupture the tank.
If you going to pull the pick up sender assembly for any reason you will need a new seal for reinstall.
 
krazykuda said:
I like the see through plastic filters before the carb. If properly located, heat is not a problem.
Click to expand...

I have read that the ethanol in gas can degrade these plastic filters. Has anybody experienced this? Sure would be a bad place to have a fuel leak!
 
I use the plastic filter when I have to use the old tank.... I can see into the filter somewhat, I change it out probably every 6 mo if I drive it 200-300 miles per week or as needed if crap in tank... never had one leak or rupture, on car with new tank I feel safer with metal filter
there are thing s we NEED to do when we pick up a new project,b ut if your like me $$$ gets in my way... a given: new gas tank, pichup, rubber grommets, clean rust mayne out of filler neck?? correct gas ca, repop lines from tank to pump, new brakes, including repop lines? a dissy that is GOOD, and vac advance works. GOOD carb? not to mention Good working trtanny rear end and engne!!?????
 
If your having fuel pressure problems and thinking about replacing the sock in the tank you might as well just drop the tank and clean or replace it at the same time this way you won't have to worry about it clogging up for another 30+ years.
 
74Dart_Girl said:
Please forgive my naiveness yet again, but how do I get to the sock filter?
Going off of what others have told me in my other post, I may need to change it. I want to be prepared to deal with it. :)
Click to expand...

Hi, young lady. If you have not done so, visit this thread

http://www.forabodiesonly.com/mopar/showthread.php?p=1970088617

Near the end and download a free service manual. The 73 manual is the latest we have. There are two parts, chassis and body manual. The sock would be on the fuel sender, and you would have to remove the sender from the tank. This is a messy job, but might be worth it.

Another problem might be if the vent system has been modified or is plugged. These girls have a vapor / emissions system to control evaporation from the tank, often called the "carbon can" which is up front in the engine bay. The tank is not vented "as such". The tank as what is known as a "pressure vacuum" cap which is intended as a sort of "last ditch" to allow pressure in or out of the tank if things build up too much. In normal operation, a 1/4" vent line goes all the way up front and connects to the "carbon can" system. This is detailed in the manual, both in the fuel sysem, and in the emissions chapter.

Also, "MyMopar" has some good downloads. Some of the third party postings has mistakes here and there, but there is a lot of Mopar native material, including shop manuals, and videos and booklets from the Mopar tech library

http://www.mymopar.com/index.php?pid=31
 
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