Not saying this is a good idea
... but.... Stihl Ultra 2 stroke oil contains 80% TMP Ester according to the MSDS
.... Extremely concentrated, but with another 20% additive package of who knows what...
I personally use Marvel Mystery Oil, Redline, and then Rislone for solvents (MMO has Naphthenic Petroleum Distillates, Redline has PAO and Esters, and Rislone has 11% TMP ester according to a lab test I saw posted on BITOG). I dont usually run these for a full OCI just because I am not a chemist and I don't think I am smarter than the chemists at Shell or Mobil... but I get some nice sludge and varnish cleaned up with them... i use small amounts to avoid seal swelling.. but we'll see how it pans out long term.
I think I would trust the HPL Engine cleaner the most, just because of how well respected it is on here. It's my next purchase once i use up my Rislone. But I do own some of the Stihl Ultra oil (i use it for its intended purpose for my 2 stroke small engines) but i cannot say i am not tempted to dilute it to like 5% and run it iwith my PCMO for esters! (like a short term engine flush before an OCI)
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