Fuel Contamination Myths: The Test Results
A head-to-head test of 1 fuel contamination myths options with the measured results for each. See how they ranked and watch the full test video.
Craftsman small engine (lawnmower), used as the test subject for the sugar-in-gas myth
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The measured results
Every number below is read straight from the test. Scroll sideways to see all measurements. Products are listed in the order they finished.
| Product | Test setup | Run time | Immediate outcome | Compression test | Teardown inspection |
|---|---|---|---|---|---|
| 1Craftsman small engine (lawnmower), used as the test subject for the sugar-in-gas myth | 16 oz of fuel mixed with a quarter cup of table sugar in a jar, shaken to attempt dissolving; sugar did not fully dissolve and settled at the bottom, so the entire jar contents (fuel plus undissolved sugar) were poured into the engine's fuel tank | engine ran, stalled once when it ran out of fuel (sugar crystals visible in the empty tank at that point), was refueled and restarted; total elapsed run time was about 105 minutes | fuel tank ended up empty with sugar residue still inside; the engine did not seize and was not destroyed | a compression test (both hot and cold) was performed after the run, but no numeric compression readings are given in the transcript | cylinder head showed a build-up/residue from the sugar; the piston also showed build-up; carbon was visible on the valve; the engine was noted as not running at its smoothest during the test |
How it was tested
- fuel contamination test: a quarter cup of table sugar mixed into 16 oz of fuel and run through a small engine (about 105 minutes total runtime) to observe for stalling or seizure
- post-test compression test (hot and cold, no numeric readings stated)
- engine teardown inspection of the cylinder head, piston, and valve for sugar residue or carbon build-up
Data notes and caveats
This is a myth-test of a single folk claim (does sugar in a gas tank destroy an engine), not a brand/product comparison, so isHeadToHead is false and winner/runnerUp/budgetPick are null. Narrator's own verdict: 'it doesn't appear that sugar is going to cause any sort of significant damage to this engine... but this could have some long-term impact on this engine' - i.e. the catastrophic-failure/seizure myth is not supported by this test, but residue/carbon build-up was observed and flagged as a possible long-term concern; that nuance is preserved rather than reduced to a simple true/false. chapterMap is false: the meta chapters ('CHAFTSMAN' 253-260s, apparently a caption typo, and 'CRAFTSMAN' 260-459s) appear to be on-screen brand-name text overlays rather than markers of distinct test phases, and do not map cleanly to the test's actual structure (mixing, running, teardown). Transcript itself is clean and unambiguous with no numeric or brand-name garbling to flag; confidence is high on data quality despite the video providing only qualitative results (no numeric compression figures).
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