I can pick up an almost new gas tank for little money. It is the model without rollover valve, vent line towards rear of truck (Part# F1A). I cannot find information on here (yes, have tried advanced search) or from Mr. Google to tell me if this is the correct tank for my truck. Anyone able to confirm or deny? Tank is behind axle. Thanks.

 

There are two differences between the tanks. Tanks with EEC have a hole in the top center of the tank. A rubber grommet and check valve are pressed into the hole. A line goes from the check valve along the inside of the passenger side frame rail to the engine compartment where it hooks up to a charcoal canister. Non-EEC tanks don't have this hole. The other difference is the nipple for the breather line that is located right next to the nipple for the filler hose is located 180 degrees opposite.
If you are going from an EEC tank to a non-EEC tank you must also change the fuel cap to a vented style. The EEC tanks are vented through the EEC system and use a sealed fuel cap. Non-EEC tanks vent through the fuel filler cap.
If you run a non-EEC tank and a sealed cap the minimum is you'll have fuel starvation problems, at worst a collapsed fuel tank.
- Is your truck a long bed 4WD? Does it have evaporative emission system?
There are two possibilities with the plastic tank.
79 F150-350 regular cab, 133" WB 4WD, w/ evap. emissions system, 24.8 gallon mid-ship plastic tank
D7TZ-9002-C
Same w/o evaporative emissions system 26.3 gallon plastic tank
D7TZ-9002-D

Also since you are putting a new tank, you might as well put in a new sending unit.

 

OP said the tank he's looking at does not have a "rollover" valve.

There's no such thing as a rollover valve on these trucks. OP is referring to the Evaporative Emission fuel vapor valve that you called a check valve.

And btw: EEC refers to the Electronic Engine Control System (aka on board computer) that no truck in the 1970's came with.

Evap/Em or ev/em are the abbreviations for the Evaporative Emission System.

 

Interesting. Most of the online parts places I checked listed tanks with and without rollover valves for these trucks. Example: Ford F100 Fuel Tank - Gas Tanks - Action Crash Replacement Dorman - 1979 1976 1981 1978 1983 1975 1977 1980 79 76 81 78 83 75 77 80 - PartsGeek.com

 

only from action crash, dorman and the other place have it wrong to but closer with the eec.

You need to look and see if you have Evap/Em for your self, as it can have either one. Easiest way is to look in engine compartment for charcoal canister.

 

A rollover valve is an incorrect term for the fuel vapor valve.

A rollover aka tip over valve function is: When the vehicle rolls over, the valve shuts off the fuel system to prevent a fire.

9B593 Fuel Vapor Valves:

 

Thanks everyone. What about the vent tube location (front vs rear)?

 

That will depend on whether you have evap or not. I think this was so you couldn't easily switch from evap, to non-evap. If you order the right one for your emissions, the vent tube will be in the right spot.

 

Engine bay: