midship plastic gas tank woes

[fatherdoug]

I have a plastic tank(original, I believe) midship on a 1978 F-150(49 state emissions) 4WD with about 22.5 gallon capacity +/- that is leaking around the top of the tank at the hose inlet area. I don't know if the leak is coming from the old cracked vent-hose or from the tank itself. The tubing that the hose connects to on the tank seems awfully loose. It doesn't pull out, but there is a lot of flex in the connection to the tank. Is this normal?

Also, I've been looking at replacement of the tank. All the listings that I can find for a plastic midship tank with 22.5 gallon capacity are for 2WD application only. Is there a difference between 2WD and 4WD midship tanks?

The midship tank is mounted inside the frame rail in a metal shroud that is in pretty bad shape. If I replace the tank, do I have to remove the bed? I can get at the fuel filler hoses from underneath, and the sending unit connection is located on the side of the tank away from the frame rail.

Any thoughts?

 

[Ronzi]

The 4wd tanks are different than the 2wd tanks. The plastic midship tanks for 4wd's are not being made by anyone and are hard to find.

 

[LEB Ben]

I always thought the midship tank was 19 gallons...and if so JBG has both the emissions and non emissions tanks...since you said your truck is 49 state, this should be the tank for you:

http://broncograveyard.com/bronco/i-20324_1973-79_plastic_19_gallon_side_tank.htm


I also don't believe you'll need to take the bed off to replace it.

 

[mrfixit]

When I had mine leak, it was just the rubber inlet gasket. dried and cracked. Gas these days is a different formulation than when these trucks were built, and rubber doesn't last anymore.
Most of the midship tanks for the F and E series IIRC were the 18 gal +/-. Even the F350.

 

[Ronzi]

I always thought the midship tank was 19 gallons...and if so JBG has both the emissions and non emissions tanks...since you said your truck is 49 state, this should be the tank for you:

http://broncograveyard.com/bronco/i-20324_1973-79_plastic_19_gallon_side_tank.htm

This is listed in the description of that JBG tank :
-Replaces original metal tank, NOT original plastic tank

The 2wd trucks have the metal side tank. The 4wd's have the plastic side tank.

 

[LEB Ben]

Well then maybe he can get some dimensions and make a couple calls. Do you have pics to see the physical differences between a 2wd and 4wd compared to the JBG tank I posted?

 

[Mil1ion]

 

[LEB Ben]

So Dennis...for those of us that aren't as proficient at deciphering those diagrams and charts...WTF does all that mean?

 

[Mil1ion]

Those are application charts.

There were so many configurations that I just post the list....


Note to FD,

Some guys are using Mustang Fuel Tanks for a replacement

 

[Ronzi]

Well then maybe he can get some dimensions and make a couple calls. Do you have pics to see the physical differences between a 2wd and 4wd compared to the JBG tank I posted?

Sadly I dont. Ive been on the look out for a parts truck with duel tanks but havent come accross any 4x4's lately. My midship tank was gone when I got my truck and Id love to get it all hooked back up. Im not opposed to making something work like the mustang tank but Id rather it be original parts if I can find some. Maybe that JBG tank can be made to work. Im not sure.

 

[BKW]

I have a plastic tank (original, I believe) midship on a 1978 F-150 (49 state emissions ) 4WD with about 22.5 gallon capacity +/- that is leaking around the top of the tank at the hose inlet area.

There is no such thing as a CA only fuel tank.

D7TZ9002D .. Mid-ship Plastic Fuel Tank ~ 26.3 Gallon / Use without Evap Emission / Obsolete

Fits: 1977 F250 4WD from serial number Y40,001 (Not High Boy).

Fits: 1978 F150/250 4WD 133" Wheelbase Regular Cab.
------------------------------------------------------
D7TZ9002C .. Midship Plastic Fuel Tank ~ 24.8 Gallon / Use with Evap Emission / Obsolete

Fits: 1977 F250 4WD from serial number Y40,001.

Fits: 1978 F150/250 4WD 133" Wheelbase Regular Cab

Fits: 1979 F150/350 4WD 133" Wheelbase Regular Cab

NO Ford Dealer or obsolete parts vendor has either one.

I just looked this jazz up for someone on t'other site a coupla days ago.

The OP said that some whizbang Bronco Graveyard employee told him the midship tanks for this application are steel and the same as 1973/79 2WD.

As y'all can plainly see...they are NOT the same!

 

[fatherdoug]

Thanks for all the info. I'm thinking this is a replacement tank, not original. The vent tube is toward the rear of the truck, which is contrary to what Dennis shows in his scanned diagrams, And I'm pretty certain the tank is at least 22.5 gallons. The one time I let the tank go empty, I put 24 gallons of gas in the tank. The tank dimensions are roughly 60" long by 12" wide by 10" tall.

I see a 24.8 gal plastic tank listed in Dennis's info for the '78 with 133" wb with evap emissions.

 

[fatherdoug]

Bill, I was typing as you were typing. Thanks for the info. It appears to be the 26 gallon. Looks like I'm screwed for an exact replacemnt. Hopefully it is just the gasket as mrfixit mentioned. Where does one find one of those?

 

[BKW]

Dennis, if you get a chance, scan and post these 1978/79 4WD illustrations: Section 90, Pages 28 & 29.

The illustration you posted in post #7 is for 2WD...a completly different setup.
---------------------------------------------------------------------------
D7TZ9F299A .. Seal-Fuel Tank Vent Connector / 11/16" I.D. ~ 1 5/8" O.D. / Fits into 1" hole in tank / Obsolete

No Ford Dealer or obsolete parts vendor has any.

FatherDoug: Without you seeing a pic of the setup, further part number searches will have to wait until you are sure of what you need.

Are you sure you do not have Evap Emission?

There is no Fuel Vapor (charcoal) Cannister? No Fuel Vapor Valve Assy in the tank?

 

[UNRULEE]

The front tank in my 79 250 is over 20 gallons.

 

[Mil1ion]

 

[fatherdoug]

Thank You, Dennis. The picture helps. It looks like the metal shroud is what holds the plastic tank in place. If that's the case, then I'm in big trouble, because about half of the bottom side of the metal shroud is rusted away.

 

[fatherdoug]

Well, I pulled the tank today. I have some pictures in my gallery. I did fill the plastic tank with water to verify the capacity. Using a five gallon container, I added 25 gallons of water, and it still wasn't overflowing.

I also looked for a part number on the tank itself, but could not find one. The tank is in very good shape, and as mrfixit surmised, it was the seal on the vent tube that had cracked and was leaking gas. The sending unit was in excellent shape, with no gas in the float, and the sock was clean. The sad part of this whole mess is the metal shroud that holds the tank in place is in really rough shape on the bottom.

So, before I try to fit an aftermarket tank, I'm going to look at getting a local fabrication man to repair the shroud, and I'm going to take the dimensions of the rubber seal to evrywhere I can and see if I can retrofit another application. I REALLLLY don't want to buy another tank for a rubber seal.

Thanks everybody for your suggestions and information.

 

[BKW]

D7TZ9F299A .. Seal-Fuel Tank Vent Connector / 11/16" I.D. ~ 1 5/8" O.D. / Fits into 1" hole in tank / Obsolete

No Ford Dealer or obsolete parts vendor has any.

In case you missed this info.

 

[fatherdoug]

Thanks Bill. I did see that. I was hoping I could find another application that might fit the tank, as in other car manufacturers or other rubber industrial manufacturers. I did find a wire grommet that has roughly the same dimensions as the seal but is not for a gasoline application.