MovieChat Forums > Back to the Future Part III (1990) Discussion > Why couldn’t Doc just make his own gasol...

Why couldn’t Doc just make his own gasoline?


Doc who knows how to make a time machine and despite how back in antiquity he went, he was able to create an ice-cube machine. By that logic, can we assume that Doc can easily create a time machine? The problem in 1885 was of course, that there’s no gasoline to fuel the DeLorean.

But since Doc should’ve known more, wouldn’t he then know that kerosene was available in 1885? Couldn't he simply track down where kerosene was being refined to make some gasoline off the by-product of that process?

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No, refining gasoline is a very advanced procedure using equipment and chemicals that didn't exist yet. There's no way Doc could have figured out the process and built the equipment in less than a week.

Further, early gasoline was very low in octane. Typical compression ratios of early cars with internal combustion engines that used gasoline was about 4:1. The DeLorean would have been at least 8.5:1 and would have detonated so badly it's unlikely the car would have gotten to 88 before the pistons melted or cracked.

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So here is my question on this: now that there are two delorians in the old west (the one Doc used to get there and the same one brought back by Marty), why not siphon the gas from one to the other? Patch up the hole in the tank or line and go!

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Typically when a vehicle has to be left unused for a lengthy amount of time, the tank has to be drained so old, expired fuel doesn’t cause problems for the engine (gasoline only has a shelf life of 4 years). Doc likely did this, and since he wasn’t expecting Marty to show up when he did, probably disposed of the fuel also, as it would’ve been deemed useless from that point.

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Great reply! I did not know that! Makes sense, but I do wish they had worked that in at some point.

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