This Scientist is an Idiot.

Dr. Emmett "Doc" Brown has invented many things. An automated dog feeding apparatus, bunch of clocks that are all off by 25 minutes, a ridiculously large guitar amplifier, etc. He's a scientist. A mad scientist, for all intents and purposes, that has mastered the lock to man's eternal jail: time.

He's also a complete idiot.

In Part 3 of the series, Marty McFly (in 1955 having just witnessed Doc and the DeLorean be struck by lightning and receiving the letter from Doc written in 1885) arrives to tell Doc's 1955 counterpart that he's back from the future. The letter basically states that Doc is happy in 1885 and he hid the DeLorean in the old Delgado Mine for Marty to use to get back to 1985. The time circuits are fried, but with the help of the 1955 Doc it should be no problem to fix them.

They find the Delorean in the mine and also Doc's tombstone. Yadda yadda yadda (we have to go back to 1885 to save Doc's life and what not.) 1955 Doc fixes the time circuits (mounted on the hood) and puts new tires on the DeLorean. They take it to the drive-in theater and Marty goes back in time and runs into the indians in 1885. He hides it in a cave (with a bear) and discovers an arrow has pierced the fuel line. Gasoline leaks into the dirt.


This means there are two DeLorean time machines in Hill Valley in 1885. One in the old (currently new) Delgado Mine and one in the cave with the bear.

We expect that the one that Doc Brown hid in the mine is in fairly good condition minus the fried time circuits. The one in the bear cave is over 70 years old. The rubber fuel line was probably fragile to begin with. But it is the Bear Cave DeLorean that they choose to attempt to escape from 1885. But there's no gas stations in 1885. They have to find another way to get it up to speed. After failing to reach 88mph with a team of horses, Doc pours the strongest stuff the bartender has into the tank and blows the fuel injection manifold out the back. Of course it does. It's a technical mechanism over 70 years old! "It'll take me a month to rebuild it," Doc says.

Right. Except you have a perfectly good fuel injection manifold right over there in the old Delgado Mine, you idiot! Just leave a note for your 1955 counterpart that he needs to replace that, too. Even if it takes 1955 Doc a month to rebuild it, it won't matter because he has a time machine. He has to fix the time circuits anyway. Why not a little fuel injection manifold as well? You have two of everything. It is literally the same car. Steal the fuel lines off the Delgado Mine DeLorean while you're in there. Or the gas in the tank...

Well, it can be assumed that if Doc thought he would be sealing the DeLorean in the mine for 70 years that he would drain the fluids from the car. So there probably would be no gas in the tank of the Delgado Mine DeLorean. That would be just too easy. But, hey, we have a scientist here. In 1885, he has already made a sick super scope rifle and a massive, barn sized freezer that makes one dirty ice cube at a time...Surely he knows the chemical composition of petrol or ethanol or some derivative better than "the strongest stuff" the bartender in a no-name frontier town has to offer? He sure knows the chemical composition of his high octane boost Duraflame logs to make a steam locomotive reach high speed. Why not make one gallon of gas to get back to the future?

Idiot.