Gas Tank and misc fuel parts replacement 302

danumkc · May 13, 2019

Hi All,

I have a slow leak coming from the fuel tank on my '73 302 Coupe. I also frequently notice a strong gas smell inside/outside my vehicle. I would like to replace as many of the fuel components as necessary and would like to get the group's opinion. Also, any idea how long it would take a novice to replace all of these items? What about a professional?

1. Fuel Tank (TF32A)

2. Fuel Tank Mounting Straps and Adapters (TNK-ST89) * Is this recommended?

3. Fuel Level Sending Unit (TNK-FG87A)

4. Fuel Tank Sending Unit Gasket (SDK-C0AF-9276-A)

5. Mechanical Fuel Pump (MRG-7718MRG, 110gph, 3/8 in)

6. Fuel Mounting Strap Isolator (SUM-939520)

7. Classic Tube Tank to Pump Lines (MUF1012-OE, 3/8 in) * Is this worth replacing? How long this would the line take to replace? Supposedly this model is form fitting.

Thank you in advance!

Dan

Don C · May 13, 2019

First, make sure it's your tank leaking and not the gasket around the fuel sending unit or the flexible fuel hoses, or connections.

Always replace the sending unit when replacing the tank, unless the sending unit is just a few months old, along with the gasket.

The straps don't usually need replacing, just depends on the condition of them.

Replace the flexible fuel hoses.

Whether or not you should replace the metal fuel lines depends on the condition of them. If the car has been sitting for a long time I would say yes, replace. Fuel lines that have been sitting for a while get condensation in them, rusting them from the inside out. They can also get varnish built-up on the inside. Force gas or carburetor cleaner through the line, into a container, and see what comes out. Any rust means replace.

You should be able to replace the tank, sending unit, and flexible hoses in a couple of hours. Make sure you get ethanol compatible hoses.

Drain the tank before you start. Safety, safety, safety, no flame or spark sources anywhere nearby. Ventilation is next on the safety list.

Replacing the entire fuel line will likely take all day.

ZIPNZ · May 13, 2019

I would also check the fuel vent tube where it comes up on the passenger side firewall to make sure it’s either capped off or connected to the fuel vapor canister. The previous owner of my car removed the canister and never plugged the vent line. It took me awhile to figure out the source of the gas smell

cv_72mustang · May 20, 2019

Hi, Just had my 72 Vert. 351C fuel tank changed with all these parts, less straps. Like post before stated about fuel lines is right, mine were TOAST! along with vent tubing. Make sure you get a fuel sender that is 'compatible' with the gauge. I'm still trying to sort out why my fuel gauge now reads incorrectly. Appears that anything over an 1/2 tank reads full on the gauge. Garage that replaced has reported issues with senders. I'm going to test myself when I get some time using some known resistors that simulates to the sender unit. It may be the voltage regulator in the cluster, maybe. BTW, was going to do myself but wife said no. Garage attached to house. LOL

Something like--> "10 -70 ohms" (Full-Empty)

Hemikiller · May 20, 2019

I'm still trying to sort out why my fuel gauge now reads incorrectly. Appears that anything over an 1/2 tank reads full on the gauge. Garage that replaced has reported issues with senders. I'm going to test myself when I get some time using some known resistors that simulates to the sender unit. It may be the voltage regulator in the cluster, maybe. BTW, was going to do myself but wife said no. Garage attached to house. LOL

Something like--> "10 -70 ohms" (Full-Empty)

All of the aftermarket senders are inaccurate out of the box. You need to calibrate them before installation.