Engine Carbon Cleaning Method: The Test Results
A head-to-head test of 1 engine carbon cleaning method options with the measured results for each. See how they ranked and watch the full test video.
Some figures on this page were transcribed from the test video and have not been independently re-verified. Treat the numbers as a close guide and watch the full video for the exact readings.
ATF Havoline automatic transmission fluid
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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 | Crankcase oil condition after infusion | Carbon cleaning effect | Cold engine compression test | Smoke level |
|---|---|---|---|---|
| 1ATF Havoline automatic transmission fluid | not milky white like the earlier water test, described as fairly clean; the old used oil had 45 minutes of use on it at the time of comparison | narrator believes the transmission fluid's detergents did a good job of cleaning up the crankcase of the small engine, calls the result very interesting | performed on camera but no PSI value is spoken in the transcript; the meta chapter titled '61 PSI Cold after ATF' (197-256s) is the only source for this figure | meta chapter titled 'Smoke level similar to Seafoam' (130-136s) claims comparable smoke to the prior Seafoam test, but this comparison is never narrated in the transcript |
How it was tested
- carbon deposit cleaning via ATF infused into the intake manifold of a lawnmower engine previously used in a water-cleaning test
- crankcase oil sample color/condition check before and after treatment
- cold engine compression test after treatment
Data notes and caveats
Sixth in a Seafoam-testing video series; only ATF (Havoline) is physically tested in this video's footage, using the same lawnmower engine from a prior water-cleaning video (a separate videoId, not extracted here). Seafoam itself is referenced only from an even earlier video in the series, not retested on camera here, despite being listed in the description's Products Tested section. The video ends unresolved: narrator explicitly asks viewers 'would you rather use seafoam, water, or automatic transmission fluid to clean the internal combustion chamber of an engine?' rather than declaring a winner, matching the channel's other undecided cleaning-method comparison videos. The only compression PSI figure (61 PSI cold after ATF) and the smoke-level claim ('similar to Seafoam') exist solely in meta chapter titles and are never spoken in the transcript; logged to data/onscreen-only.txt for video-frame recovery.
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