Originally Posted By: Indydriver
Originally Posted By: Garak
If you want the fuel out of the oil, you either need to get the oil up to sufficient temperatures or simply change it out.
You know, I've read this a hundred times on BITOG and I'm wondering if anyone has actually proved this? It's not like my car is never driven over four miles at a time. A couple of weeks ago, I drove 120 miles a day two days in a row. I question the theory that you can drive fuel dilution out of the crankcase.
It would be more accurate to say that bringing the oil up to temperature every time an engine is started will prevent fuel dilution. Once fuel has been allowed to accumulate in the sump through successive cold starts without the oil coming fully up to temperature, may become permanently diluted, at least in part as I understand it at the molecular level. (I think we would need Molekule or some of the other chemists or tribologists on board to give a more precise description of what actually happens.)
Aside from reducing the oil's viscosity this does not seem to reduce an oil's lubricity. As long as oil pressure can be maintained and the TBN level is not depleted there is no real need for concern.
The real problem in not bringing the oil up to temperature every time the engine is started is that the AW additives will not be entirely activated and therefore repeated cold starts and cold running will result in increased engine wear.
Originally Posted By: Garak
If you want the fuel out of the oil, you either need to get the oil up to sufficient temperatures or simply change it out.
You know, I've read this a hundred times on BITOG and I'm wondering if anyone has actually proved this? It's not like my car is never driven over four miles at a time. A couple of weeks ago, I drove 120 miles a day two days in a row. I question the theory that you can drive fuel dilution out of the crankcase.
It would be more accurate to say that bringing the oil up to temperature every time an engine is started will prevent fuel dilution. Once fuel has been allowed to accumulate in the sump through successive cold starts without the oil coming fully up to temperature, may become permanently diluted, at least in part as I understand it at the molecular level. (I think we would need Molekule or some of the other chemists or tribologists on board to give a more precise description of what actually happens.)
Aside from reducing the oil's viscosity this does not seem to reduce an oil's lubricity. As long as oil pressure can be maintained and the TBN level is not depleted there is no real need for concern.
The real problem in not bringing the oil up to temperature every time the engine is started is that the AW additives will not be entirely activated and therefore repeated cold starts and cold running will result in increased engine wear.
