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1940 Ford Truck Question

Hi. I need some help. I’m a screenwriter and in a scene I’m working on a character drives a 1940 Ford pickup (the story takes place in the 1940s). In one scene the truck stalls/breaks down on the side of the road and the grandfather fixes the truck, at least temporarily, with his grandson’s help. I don’t know much about car repair. That’s why I need help. I need ideas as to what could cause the truck to stall and how it could be fixed using tools a farmer would have his truck. A simple flat tire won’t suffice, as the scene needs to show the grandfather’s mechanical know-how being passed down to his grandson. Any ideas?

If you can write the scene for a hot (very hot) day the truck could get vapor lock. The fix is to pour some water over the fuel line between the fuel pump and the carburator. Old trucks could get a weak fuel pump, with low fuel pressure the truck would run fine, most of the time. On a hot day when you slow down the temp in the engine compartment could get hot and the fuel in the line can “vaporize” and the truck will stall, just like it is running out of gas. If you don’t have water you just open the hood and sit there for 15-20 min for the engine to cool, restart and drive away.

Otherwise actually those old trucks rarely stalled. If they started they ran. He could carry some spare parts like a spare ignition coil, and a spare distributor cap. The plastics in the old cars would crack over time and I had to replace a couple of distributor caps when traveling on the road. Usually the car would just run like bad and miss badly but I guess you could stall it out.

In my '61 Mercury I carried a spare fuel pump, water pump, distributor cap, and set of points in the truck along with some basic tools. I ended up changing out the water pump in the middle of a trip through the mountains.

The truck could stall because of a stuck float in the carburetor. Easy fix with a screwdriver and a pair of pliers and an adjustable wrench.

Gas pedal connecting rod link falls off on way to church on a Sunday morning. Gramps wirers it back on with a small coil of wire he always keeps under the trucks seat. Etc.

One possible scenario is that the distributor points closed up and therefore the ignition failed. The grandfather unclips the distributor cap, scrapes the contact surfaces of the points with his pocket knife, sets the point gap with a thin dime (that was about the .020 of an inch), restart the truck and he would be on his way.

If he didn;t have a dime, a matchbook cover .017 would do.

He could discover the stuck points by removing the air cleaner and setting it carefully down (it has oil in it he doesn’t want to spill or get dirty). He then looks down inside the carburetor and works the throttle linkage once and tells his grandson “yep-it’s got gas” . He then has his grandson turn on the key and crank the starter while the grandfather uses a rad, glove or sticks to hold a spark plug wire 1/4 inch away from the head. He then announces “no spark” and removes the distributor cap and discovers the stuck points.

Not buying “stuck points”, but they did burn a lot back in the day. It was an easy fix with a points file which a lot of people carried in their tool box back then. I know I always had one in my car along with a few basic tools. I still have one somewhere but I haven’t even see on for sale anywhere lately.

In place of a points file, I have used an emery board (for filing fingernails) and I have used emery cloth. Most types of sandpaper and fingernail files do not work as the points are made from a very hard material. Then they could be adjusted as above.

I don’t recall any one stalling while driving, usually the problem with points would show up when you went to start the vehicle, so for this to work, you character would have had to stop for some reason and when he went to leave, the truck fails to start.

Probably the most common reason people would have to pull over was the radiator overheating. They seldom used antifreeze back then, and when they did, it was alcohol based and would evaporate easily. Back then you could tell when someone was traveling because they would have a water bag hanging on the front bumper.

The water bag was square, like a handbag, and made from a white canvas type material and it was hung on the bumper to keep the water cool. It held about a gallon of water. It could also be used to cool the fuel line.

If you want to make the repair more extensive, he could have blown a radiator hose. They would usually give out right at the clamp and many time you could loosen the calm, cut off that end of the hose, about 1", and re-clamp the hose in place. The hoses usually had enough give in them to do this one time.

Another thing that would happen with the “three on the tree” manual transmission is that the shift linkage would hang up between the one two shift if you moved the stick too fast. You would have to open the hood and manually move the first gear lever to the neutral position in order to sift again.

I’m not sure that a 40 ford would have had a column shift though. This did also happen to floor shifts with the side shift on the transmission, but not very often and to free it would require getting under the truck. However, most floor shift transmissions in those days were top loaders.

@Keith–Ford began phasing in the column shift on its pickup trucks in 1950. I had an Uncle who owned a 1940 Ford Pickup truck and waited until 1951 to trade it in so he could get the column shift. The advantage of the column shift was that 3 people could ride more comfortably without the gearshift being in the way. I am certain that the 1940 Ford pickup trucks all had floor shifts.
When I was a kid, I believed that any proper pickup truck should have a floor mounted gearshift. When GMC and Ford introduced the automatic transmission on their pickup trucks in 1953, I thought it was terrible and the world would probably soon come to an end.

Keith- I think you have the 40s confused with the 30s. The was still alcohol based antifreeze on the market in the 40s, the only people that I knew that used it were people who had a cooling system leak and were postponing fixing it. As far as stuck points go, if people neglected changing their points, the gap would slowly close because the rubbing block wore down and the point surfaces would get rougher and rougher due to material transfer, The high spots on one side would mirror the low spots on the other side and once they got close enough the points wouldn’t get enough opening tension to overcome the friction between the surfaces. It wasn’t necessary to file the points to make a roadside repair to get you home. A scrape from a jack knife and re-gapping them would do the trick.
I never saw a car with a water bag in western NY state. They were common in the southwest.

Uncle Turbo grabbed my idea, the vapor lock would be ideal for that scene.

“The was still alcohol based antifreeze on the market in the 40s…”

I can tell you that some retailers (Pep Boys for sure) were still selling alcohol-based antifreeze in the late '50s!

I don’t think that many folks still used it, but if they wanted it, Pep Boys (and likely a few other retailers) had it on their shelves.

oldtimer 11, While ethylene glycol was available, I don’t remember many people using it until the 60’s. Before then, it was kind of expensive when compared to water with a water pump lubricant and corrosion inhibitor and when compared to alcohol.