Loyal viewers may recall back in November, when I asked the momentous question, What modern factory-type fuel pump actually works?.

To recap: A year before last November, I bought a very original, unmolested 1964 Dart sedan with 38,000 miles on it.
I spent a good deal of time replacing all of the things you normally replace, adjusting all the things you normally adjust, and lubricating all of the things you normally lubricate, including all fluids, disassembling and greasing the driveshaft, rebuilding the carburetor, swapping the 13" bias tires for 14" radials (couldn't get 13" white walls at a sane price), and changing the rickety plastic fuel filter for a high-quality original-style Wix 33027 steel fuel filter.

The previous owner had replaced the coil and the fuel pump, and nothing more.

I put about 800 miles on it through the year and it behaved pretty well.

Come November, it started to misbehave a bit.
At first I wondered whether the tank level was lower than the gauge said, and the pickup was out of the gas when driving up hill, or whether the vent was blocked, but I checked both things, and they were fine.
It just seemed to stumble a bit if I really got on it, or drove up hill.
So I said, "Ah HA! Fuel pump!"
I went to NAPA, bought a fuel pump [call it FP#2], replaced the new-looking DuraLast pump [call it FP#1] with it et voila! carburetor fuel fountain. New NAPA pump was pushing 8psi.
So I bought a NOS AC 6972 [call it FP#3], installed it, drove car, ran great, problem solved.

Until this Spring.
Started it up, drove it to work (100 miles round trip), by the time I was almost home, it was as bad as it'd been in the Fall (it's embarrassing to drive up the long hills halfway off the road to the right at 15mph in a 55 zone, when you don't even have emergency flashers).
Damn. 50 year old FP#3 must have gone bad.

So, I dd a search, found a NOS Airtex 6972 fuel pump [FP#4] for a reasonable price. Seller listed it for a \6. Bought it.
Pulled FP#3 off. Turned it upside-down. Thick rusty gasoline came out. Yuck.
Couldn't get the damned thing installed. Pump looked the same, base was the same, gasket was the same, lever was at a slightly steeper angle, and I just couldn't quite get it to line up inside the block.
I played with it for days.
Finally the idea hit me: What if it's the wrong part?
So I did a search. "Fits Chrysler 400 '73-'77."
SOB.
Same number as the AC, different pump. I mean, MF. If I ever run into the guy who set up their part numbers...

So, I did another search, found a NOS NAPA / AC 95-6972 [FP#5] for a reasonable price, bought it.
Installed it pretty easily (the right part fits much better than the wrong part).

Because of how yucky the fuel inside FP#3 had looked, I had bought a clear plastic fuel filter, figuring I could put it in the hose between the pickup and the hard line, to see whether I could keep some of that dirty fuel out of the pump. Plastic fuel filters concern me on the pressure side, but should be okay on the suction side.

So, the new fuel pump is in, I'm messing with the distributor (its next door neighbor), thinking about installing the plastic filter, thinking about how to orient it in case it fills up with crud, and I look up and see the metal fuel filter attached to the carburetor.

And I stop.

And I grab a pair of Vise-Grips, release the spring clamps, pull the metal filter out of the hoses, and blow on the end.
Nothing.
I can't blow through it.
I replace the metal filter with the plastic one I have.

Reassembled, the car runs great.

The moral to this story: Steel fuel filters are great, look good, and are what you should use.
Unless you are resurrecting a car that's been sitting.
In that case, for the love of all that is Holy, use a plastic filter, and you can watch to make sure it isn't filling up with gunk, and save yourself from buying Fuel Pumps #2 through #5.

By the way, so far, no crud visible in the plastic filter.

And now, for those patient enough to have read all the way down to the bottom, a Bonus Question:
The car's steel fuel line has a 1/2-20 flare fitting.
The DuraLast pump, the NAPA pump, and the (wrong) Airtex pump all had 1/2-20 flare outlet fittings.
Both of the AC 6972 pumps have 3/8-24 flare outlet fittings.

Why is this? Nobody makes a single adapter fitting for this. I had to use two fittings to get the pump to mate to the line.

Inquiring minds want to know.

Thank you for listening.

/rant

– Eric

Glad you got it figured out!

The best idea I have seen when resurrecting an old car that has been sitting is to daisry chain about five clear plastic fuel filters together before the first startup. Then you can see if there is crud coming through the line. If there is, you just remove the filter closest to the tank when it gets clogged, then repeat until the filters don't clog anymore. Then install a single metal fuel filter and be done.

_________________
Casually looking for a Clifford hyperpak intake for cheap.

Interesting idea. I had considered something like this, but wasn't sure how much resistance the 3-4psi fuel pump could push against.

In practice, that is essentially what I did, with a bit of a "detour." :rolleyes:

The clear plastic filter has thus far accumulated no crud at all.

(Oh, and before someone mentions it, I did replace the pickup screen when I got the car, and I've got a spare I'm going to install the next time I've got it opened up).

– Eric