Originally Posted by
GXPmach
Actually the Seafoam MSDS lists Pale Oil, Naptha and IPA. The only constituent dramatically different from fuel is the IPA. While ethanol and IPA are different, you are correct the ethanol content will be rising anyways probably.
IPA in oil won't have any "drying effect." I'm not even sure what you're trying to imply there. The IPA will act as an antioxidant yet the radical products should readily vaporize on startup. It would be no different from the long chain antioxidants in oil additives...I'd guess hindered phenols, but that's neither here nor there. Either way, these are simply less reactive, but heavy enough to stay in solution at temperature and pressure. The IPA would likely get up to pressure and readily pass into cylinders during the intake stroke. A very low quantity won't blow out oil pressure either...some of this already happens with mineral oils anyways.
"Steam cleaning" which is actually steam oxidation, can readily destroy deposits as well. The real purpose is to simply get the system running lean so that oxygen can attack deposits. This, however, is an extremely slow process with steam at this temperature (Obviously it is less reactive than pure oxygen). Really low steam quantities for extended periods would be best (hours). Or even a little oxygen introduced beyond the oxygen sensor.
Overall, may I address that this may help the engine to soften and dislodge some deposits, but the problem (which is much more severe in aircraft turbine engines) is hard to correct. Many practices have been made to attempt to "clean" aircraft fuel nozzles. As of yet, nobody has been successful. The whole system gets replaced.
The real solution is cooling your fuel injection system at the design level. Either way, it ends up more cost effective to simply do a few lean burns and then eventually replace the injectors.