Packard Forum Index » Pre-War (1899-1942)

Many older Ford V8s suffered "vapor lock" as a result of a worn fuel pump actuating rod. The pushrod that operated the pump would eventually wear down and reduce the pump's stroke. This condition usually showed up in hot weather, and in extreme cases, even in cold weather once the engine warmed up. The cure was simple: Replace the worn pushrod.

So very true, I ran a '38 Ford pick-up for years through from April to October and never had an issue. When all parts are to spec most of the 'gremlins' go away.
Bob J.

The clothpins theoretically acted as radiotor fins. I have never used them but those that did would swear that it worked. As for the old flatheads it was common to put one or sometimes two flat washers in the fuel pump arm. it almost looked like it was made for it .

Quote:

I think the practice of using clothes pins on fuel lines to stop vapor locking came from the time when updraft carburetors were being used and fuel ran into them by gravity. Since there was no pressure in this supply line the fuel was subject to bubbling and vapor lock. The clothes pins would provide more surface area for the fuel line and help to prevent this condition. I have seen clothes pins with the Ford logo printed on them as they were a popular "fix" in the Model T era.

Keeping the fuel pump as cool as possible would also help prevent vapor lock. A common practice back in the day was as described. It worked.