Plymouth Fury III I really need some help!

Maintenance/Repairs
1

I have a 72 fury III with a 400cid plant
I have replaced the tank,sending unit, fuel pump, and filters.
and the carb.
the car sat for 15 years and the tank was full of a five gallons of rusty gas.
will all the new stuff installed it fired up fine for a week, every time
then if it sat for a day or so it needed a shot of ether to fire up
now there is no gas in the filter south of the fuel pump, no gas runs out when the hose is undone.
I thought we had been siphoned and so i put 5 gals in the tank

nadda

this a nice old sled and we really want to use it daily. what did we miss?

2

I had the same problem with my 1978 Oldsmobile. I would have to give it a shot of ether or prime the carburetor if it sat for more than a day. The problem turned out to be the fuel line–a section of neoprene line down by the gas tank had disintegrated and was sucking air. When I would prime the engine, the increased speed of the the mechanical pump when the engine fired would allow it to draw in the fuel. Easy fix, but difficult for me to find.

3

Thanks for your 2 cents, however, there is a new fuel sending unit in the tank.
I guess it could have failed

4

You might check the fuel line from the tank to the pump for a pinhole leak or a section that may have deteriorated. This may not be the problem, but it won’t cost you anything to look.

5

I think you might have two problems. One is in the fuel lines, either a hole as suggested already, or there is rust inside the lines either clogging the lines or clogged up the new filter.

second, I think your new carb is leaking. It should hold enough fuel to not only start the next day, but get you a couple hundred yards down the road.

6

when you say leak in the carb. do you mean the floatbowl has a leak?

7

does anyone know if this model had any valves or possible areas of obstruction from the tank to the motor?

8

I think these had neophrene float bowls. Perhaps some dirt lodged between the needle valve and seat letting the carb drain into the manifold.

9

2 barrel or 4 barrel carb? Holly or Carter?

It is possible to pressure test the fuel system in this car for leaks by pressurizing the tank SLIGHTLY with compressed air…One method I’ve seen used is to stuff a rag in the filler pipe opening and then slip in an air chuck and carefully blow some air past the rag into the tank to SLIGHTLY pressurize it. Any leaks will quickly become visible…The rag in the filler becomes your safety valve…There are rubber sections in the fuel line in several places, some hidden, like on top of the tank…

10

It i a 2 barrel. Unk what kind. I did ask when it was sent and it has a brass float

11

It sounds like some kind of blockage - disconnect the line from the pump to the carb, put the open end into a jar, and see if gas is pumped into the jar. If not, start working your way back to the tank and find out where it’s blocked. If there’s gas at the carb, then there’s a problem with the carb and it needs to be checked out an possbly replaced.

12

Yes, I meant in the fuel bowl. It should hold about a half a cup of gas, more than enough to start the vehicle weeks or months later, even if the fuel pump is not working.

If the fuel line is clogged so badly that the engine is not getting enough fuel to fill the bowl in the first place, then you should notice that while driving it. It would cutout when ever you tried to accelerate hard, go up a hill or run at freeway speeds.

The stock 2 barrel has metal fuel bowls and brass floats. Was this carb a reman or rebuild or one from a junkyard? If from a junkyard or some other source of used parts, the seal between the fuel bowl and the throttle plate could have dried up and is leaking.

13

Yes, I meant in the fuel bowl. It should hold about a half a cup of gas, more than enough to start the vehicle weeks or months later, even if the fuel pump is not working.

If the fuel line is clogged so badly that the engine is not getting enough fuel to fill the bowl in the first place, then you should notice that while driving it. It would cutout when ever you tried to accelerate hard, go up a hill or run at freeway speeds.

The stock 2 barrel has metal fuel bowls and brass floats. Was this carb a reman or rebuild or one from a junkyard? If from a junkyard or some other source of used parts, the seal between the fuel bowl and the throttle plate could have dried up and is leaking.

14

it was a brand new carb from a outfit out of jacksonville. I can try this stuff this weekend

15

i tried using a mason jar of gas south of the filter and pump, now the pump makes noise, but it doesnt seem to pump

so looks like that is a great place to start. this car has a new mechanical pump on it but the fella who worked on it when we got it said that electronic pump is better , the mech one is new I put it in , think i will try hooking it up, there are two trees, one points down and the short tree is at 90 degrees, anyone know which is intake and which is output?