Old Truck Problems?

ford
f100

#1

Hey there!

I’m writing a story and need the help of someone well-versed in engines (because I don’t know anything about them). What are some issues that might crop up in an older truck–think '68 to '72 Ford F100–that would require a seasoned mechanic to fix?

My character basically lives out of her truck, so she’s got a good grasp of routine maintenance and small repairs. But then it goes and breaks down because of an issue that she doesn’t understand well enough to fix. Preferably it would be something that requires one or more replacement parts but won’t need to be fixed again for a long time.

Any suggestions would be very much appreciated, and personal anecdotes are more than welcome…as long as you don’t mind me stealing details to build a more realistic depiction of my character’s experience, that is. :slight_smile:

Thank you!


#2

The plastic teeth on the cam gear failed.

That was easy!

Tester


#3

Another would be carburetor problems. Such as the accelerator pump failing, or the choke mechanism sticking.


#4

Had my 72 f100 till 1990, now the $400 high pressure steering hose went out in maybe 82, got pumped up arms living with manual steering the next 18 years, Towing my 71 Nova back from ND, the fuel pump went out, managed to find a Napa in Black River Falls WI at 4 pm on a Saturday, was a balmy 18 degrees changing out the fuel pump in their parking lot, good thing that was the solution as they closed at 5. Gave the truck up, the floor pans were rusted out, the frame was going and it felt like in turns the truck wanted to go 2 different directions, Other than that no major problems for 22 years of use.

Non and regular maintenance stuff, coil, plugs, spark plug wires, points, rotor, distributor cap, accelerator pump diaphram, adjusting choke pullof, carb cleaning, vaccum advance, maybe bearing or 2, and of course brakes tires and fluid changes. Boy we used to have fun :wink:


#5

A plugged up carburetor causing the engine to cough, sputter, and stall is pretty common problem for engines of this era. On old trucks that aren’t driven much, flat tires of course are another problem that’s happening all the time. I had to rebuild the carb on my own Ford truck of similar vintage, you can probably find the thread here how the process went. And I authored a thread here about some experiments to see if I could repair a truck’s flat tire by myself, by hook or by crook. So you might search out those two threads for some ideas. I lay claim to a certain amount of fame about the truck carburetor rebuild I did. I was nominated for taking longer than anyone else ever has taken to rebuild a carburetor … lol … maybe you can figure out a way to put something humorous like that into your story … best of luck …


#6

How about a severely worn distributor gear, causing a no start . . . ?

That seems believable on an older truck, I would think

The repair would require either replacing the gear at the end of the distributor shaft, or the whole distributor. And you’d need a timing light after it was running, to properly set the ignition timing. Can’t imagine a timing light just happens to be in everybody’s glove box, so that would involve a mechanic, or at least somebody with a good tool collection


#7

Not a truck but I could not believe Ford installed a pot metal sprocket nylon cam gears on my 406cu in 405hp Super high Performance 1963 Galaxie. Especially when they installed 427 cu in style cross bolted main bearings! After the expensive failure I installed proper TRW all steel double row gears and timing chain. The Ford de-stroked 390 cu in forged steel crank 360 cu in truck engines are nearly indestructible when the “tinker toy” cam sprocket is replaced.


#8

Trucks (and cars) of this time period all had weak ignition systems that required periodic maintenance to keep them running…“Points” (ignition points) had to be cleaned, reset and adjusted…If this was neglected, the vehicle would become harder and harder to start and finally would refuse to start. A “tune-up” every 12,000 miles was a standard maintenance requirement…Plugs, points and condenser were replaced and the timing and dwell set. Usually done in the fall to get the vehicle ready for winter…Ford pick-ups of that era could be had with a wide variety of engines, both 6 and 8 cylinders…Small V8’s (289 &302 cu in) Big Block V8’s (352 & 390 cu in) Most of the six cylinder trucks were 300 Cu In, farmer trucks, workhorses that would run forever…Most of these trucks were stick shifts, 3 or 4 speeds. As they aged and the miles accumulated, the clutches could be expected to fail, making the vehicle impossible to drive and requiring a professional repair…


#9

Never really understood Ford’s switch from simple but far superior Holleys to crappy puzzling difficult to repair Autolite carbs with mystery parts. I guess manufacturing their own carbs saved a dollar or two. Unrelated but I acquired a 1966 Impala 2 door for cheap in the late 1980s. It was a go to work and back car 283 cu in 2v with 2 speed powerglide A/T but was in decent condition. The 2V “Rottenchester” carb crapped out and I didn’t feel like re-building it. I removed it and went to a local independent parts store that I had always trusted. They had a rebuilt for $26 but suggested a new Holly guaranteed perfect replacement for $23! Sign me up! It was a perfect fit and the old Chevy ran great. I wonder if Holly has these replacements for Ford Autolites?


#10

How expensive do you want the imaginary problem to be?
Do you want it to be repairable or non-repairable?

Alternately, you could always describe for us how the character’s vehicle broke down (the symptoms he/she experienced) and we could offer possible causes. There are 10,000 possible ways a truck can break down, and a description of the imaginary failure could help us trim the possibilities to a manageable number.


#11

Ok, how about a burnt exhaust valve? Let us assume it is the venerable Ford 300 cubic inch straight 6 cylinder.

Service requires the cylinder head to be removed ( a few hours), valve or valves replaced and the valve seats re-machined. The head removal could be done by the owner in a spot that the truck can stay. It requires at least a day in a machine shop. You can stretch that as long as you need for the story line because the shop is backed up with work. It then takes another few hours to re-install the head by the plucky owner or a repair shop as needed for the story.


#12

Holley has model numbers which are similar to the 2 barrel Autolite 2100 & Motocraft 2150. Can be obtained in 4 barrel too, as 4100, 4150. I think the applicable Holley’s are bolt on replacements to the Ford part.

Holley’s are easier to understand and rebuild? hmm … I read a tech book a couple years ago on the principles of operation of the Holley carb and the rebuild process. I didn’t find it any easier to understand than the Ford version of the carbs. The main advantage of the Holley seemed to be the maxium air flow supported, and that the air bleeds can be changed just by swapping in another part, similar to changing the jets.


#13

One funny story I can relate about my dad’s Ford truck of that era. Whenever he did a diy’er tune-up my pre-teen job was to sit on the top of the radiator & hold the flashlight while the changed the points and condenser. After I had done this a few times I could pretty much guarantee he was going to drop the little hex nut that holds the points into the distributor. Then I knew I’d have to hold the flashlight while he tried to fish it out using needle nose pliers. This could go on for hours, one swear word after another … lol … and help me should I ever turn the flashlight in the wrong direction even for a second … lol … one time I suggested he remove the distributor, turn it upside down, and shake that little hex nut out using gravity … omg!! you’d think I was telling him to design a moon rocket, he’d say if the distributor is ever removed, the engine will never start again … lol .


#14

Vapor lock issues.