Gas tank capacity

[51Deluxe]

As mentioned in another post, I believe I ran out of gas on an excursion  over the weekend. Put about 2.5 gallons in it to get home , drove about 25 miles before refilling, an estimated 1.5 gallons used. So there should have been only a gallon left in the tank, and the capacity is listed at 17 gallons rounded off. So it should have taken nearly 16 gallons to fill it up, and it took only 12.2.

Any explanations? The car stalled in the middle of the road. That's fine if it was out of gas, but if not, I'm concerned it will do it again in traffic.

[joefrazer]

The bottom of a 51 tank should be flat. Most have become concave which allows the fuel pick up tube to ride high in the tank. If the tube is even an inch off the bottom, you'll lose access to about 2 gallons of fuel. And, if there's a hole in the line in the tank, as soon as it's exposed, the car will starve for fuel. My 51 did that.

[Gordie]

The filler neck usually contains an extra gallon of gas if the tank is full to the brim.  Why not start out with a full tank and record your mileage and see how many miles you can go before it gets low.  With normal driving you should get close to 15 miles to a gallon.

[51Deluxe]

I'm also wondering if the design of the filler neck causes the gas nozzle auto shutoff to do it's thing early. Maybe I could have put in a lot more if I filled to top of the filler?

Anyone with a 51-54 know how many gallons your car usually takes when about out of gas?

[Gordie]

The '51 owners manual says the capacity is 17 gallons so if it is completely empty it should hold that plus what ever goes into the filler neck.

[joefrazer]

The filler neck design, along with the shallow tank will cause a gas nozzle to shut off early. You'll learn the trick to filling a 51-5 tank...slow and steady...

[dusty]

The tank could hold 17 Gallons if ihe bottom isn't pushed in. But more important  the filler neck does not go to the top of the tank with a breather tube so it will not fill completly, so as mentioned SLOW and EASY

[retired wrench]

 Saw a case where the wrong gas cap was used and fuel pump sucked the top of the tank down. You couldn't see it till tank was removed.

[BigDave LM6174]

The trick with California gas pumps is to go slow and steady.  Takes longer, but the nozzles in California have back flow covers and the filler neck causes back pressure.  My 51 is filled up at the 1/4 mark on gauge, and it is usually 10-12 gallons to fill it.

[51Deluxe]

So yours takes 10-12 gallons even when about empty Big Dave? If so, that's on par with mine. My main concern is that my car quit due to something other than being empty, and I'm about to drive it to a show tomorrow in another town.

Fred

[BigDave LM6174]

I have never let it go below a 1/4, so don't know