Ignite gas with a pay phone.
In order to escape from a dinner, MacGyver opens all the gas outlets in the kitchen to fill the building with gas. He then takes apart a pay phone and disconnects the ringer. Super old pay phones (what’s a pay phone?) have a mechanical oscillator that rings a bell.
Can you use this to make a spark? Oh, yeah. In fact, I used a very similar in a version of my spark gap generator radio transmitter.
Boom crane with a ladder
In order to get some heavy pieces on top of a house (to rebuild the roof), MacGyver uses a rope running over a movable ladder to act as a type of crane. I thought I had a pre-show sketch of this, but I couldn’t find it.
Fixing a flat tire
The truck has a flat tire. MacGyver needs to do two things—plug the hole and fill the tire. To plug the hole, he uses a bit of rubber and heats it up. Then you just push this through the hole in the tire. That’s it. Honestly, I have done this with an actual flat tire and I was surprised that it worked.
For the air, MacGyver connects the tire of the scooter to the truck. Yes, this would add some air to the truck tire from the scooter tire—but only until the two tires reach the same pressure. That might plausibly be enough air to get you going, but likely not.
If you want to get more air from the scooter tire, you could heat it up. When the air in the scooter tire increases in temperature, it increases in pressure. You need the scooter tire pressure higher than the truck tire to get a transfer.
Black pepper on a gunshot wound
One of MacGyver’s friends gets shot in a bank. MacGyver needs to stop the bleeding. Oh, here is some black pepper. Yup, that seems like it would work. https://knowledgeweighsnothing.com/how-to-stop-bleeding-with-black-pepper/
A basic radio really isn’t all that complicated. You need a capacitor, a coil of wire (for the inductor) and some type of diode. Soldiers used to make them from scratch on the front line in WWII—they were called foxhole radios.
Here’s a more detailed post about this simple radio—https://www.wired.com/2016/05/go-ahead-connect-inductor-capacitor-see-happens/
Ok, but what if you want a two way radio? Yup, it’s much more difficult to transmit. But still, you get the idea. Here is a sketch from the show notes.
Dye pack explosion
So these banks have these exploding packs of dye. That way they can toss them in with some money when bad guys steal stuff. Some of the packs are radio activated, but others go off (after a delay) when passing out of the main bank area. https://en.wikipedia.org/wiki/Dye_pack
MacGyver just puts one in a coffee cup and tosses it past the door. Since it makes a noise, the baddie goes to investigate and BOOM. Ink in the face.
Ethernet rope ladder
MacGyver makes a rope ladder out of ethernet cable so that people can escape from a second story window. It might take a while to make, but this is fairly legit.
I honestly can’t remember the exact kind of bomb MacGyver is making here—and that’s fine because I wouldn’t tell you anyway. But he uses some stuff from the bank to get into the sewers below.
Falling telephone pole
For the last hack, MacGyver hits a telephone pole that’s ready to fall over anyway. The pole falls and lands on the bad guys car. The end.