How steep is too steep?

[Allen Banks]

Coming back from a tour today...I had less than 2 gallons in my 23 oval tank. Was going up a fairly steep drive...slowly. It was about 250 yards long. It leveled out for about 100 yards and then all of a sudden the car quit. Ran flawlessly for about 70 miles today. I checked the fuel, got back in and it fired right up. So did I starve it going up that hill? I have a hard time thinking I did.

[MichaelPawelek]

Probably so. There are period writings of folks occasionally seen having to back up hills with low gas tank levels.

[Scott_Conger]

You approached a 3 gallon hill with 2 gallons. The result is predictable.

[Oldav8tor]

Yup, that would be my guess. Even if you weren't totally starved of fuel, the angle between the tank and the carburetor would result in significantly lower fuel pressure.

Somewhere I saw a old photo of a sign at the bottom of a steep hill that listed the minimum gallons of fuel needed in your tank to make it up the hill. Not a new problem with Model T's.

[Art M]

If the hill has a 6 per cent grade or greater, I suspect the engine was starving for fuel.
The steepest hills where I drive are 8 per cent, which requires at least a half tank of gas. 9 gallon oval tank.

I always keep the tank more than half full. 90 mile limit

Art Mirtes

[John kuehn]

We need to remember that Model T’s DONT have a fuel pump. The less gas you have in the tank the less pressure you have for the gas to flow faster. And that’s even on level ground!
Old tractors will have the same problem if you get to low in gas.
As I remember Ford didn’t have fuel pumps on his cars till 32. I maybe wrong so somebody can correct me.

[TXGOAT2]

The cars with the tank under the seat will run out of gas on an incline if there isn't much gas in the tank. Another possible issue is that if you have any debris in the tank, running with a low fuel level will allow the gas in the tank to slosh more, and may stir up the debris. The late Model Ts and Model As had the fuel tank mounted up under the cowl, almost over the carburetor and well above it, which increased the available fuel pressure and reduced the length of the fuel line, even when the level in the tank was low.

[TXGOAT2]

Many modern replacement carburetor needle and seats are not well suited for use on Model Ts. They are more flow restrictive than the original parts and can result in fuel delivery problems, especially with the cars with the gas tank under the seat.

[Norman Kling]

I have two ways to get to my house from town. One is around 8% the other around 6%. I need about 1/2 tank to get up the lesser grade with my oval tank. Fortunately there is a gas station at the foot of the hill and I can check the gas and fill up if too low. It has quit at least once and I was able to coast backward enough to be able to turn around and go to the station. I also have a 26 with Ruckstell. I can go up the steeper grade with Low Low. However I would rather go up the less steep grade because not only is the gas gravity fed, but also the oil to the front of the engine could get low and cause bearing wear. I use auxiliary oilers on all my T's.
So I would recommend that you keep the gas up before going up the steep hills and if there are no stations near the foot of the grade, carry spare gas with you.
Norm

[Rich Eagle]

This is too steep for our Speedster with a full tank.

We backed up the last 2 miles of the Jackson (WY) pass years ago. Had we filled the tank at the last stop it would have made it fine. A bus load of foreign tourists pulled out and watched the event. I believe this illustrates how different a full vs empty tank would be.
Rich

[MKossor]

Clever and informative illustration Rich
The picture is worth 10,000 steps to the nearest gas station