2007-01-15 07:26:16 · 4 answers · asked by PrettyEskimo 4 in Cars & Transportation ➔ Maintenance & Repairs
Coming from a seasoned certified mechanic, it amazing how so many people think that blow by plays a major role in darkening of the motor oil. What alot of folks are forgeting about is something called thermal break down. Thermal break down has about 78% of a role in making the oil dark as well as wear and fricton. Blow by only has about a good 12% of it having to contribute to the oil darkening process. New and realtively new cars only produce a small amount of blow by within the upper single digit #'s. Neglected engines have more. performance built engines are in the 8% percentileor less.
2007-01-15 12:07:04 · answer #1 · answered by vankstwer 3 · 0⤊ 0⤋
Never heard the term blow over! perhaps you mean blow by? Blow by happens in all engines and is caused by combustion gas escaping from the cylinders into the crankcase through the piston rings( blowing by the rings, get it?) and only becomes a problem when excessive, which would indicate bad piston rings. A compression test will tell you if you have excessive blow by.
2007-01-15 07:43:17 · answer #2 · answered by Galileon 2 · 1⤊ 0⤋
It's called blow by. Compression gasses under extreme pressure get past the rings and get carbon into the oil. This is normal and controlled by the PCV valve.
2007-01-15 07:33:39 · answer #3 · answered by Lab 7 · 2⤊ 0⤋
added carbon to the motor oil (making it black)... All engines do this and it is absolutely normal...it is dangerous (rings are going) when there is blue smoke comming from exaust
2007-01-15 07:30:21 · answer #4 · answered by silverback487 4 · 0⤊ 0⤋