Switching eng. oil from Mobil1 --> Shell helix *need advi

MMamdouh · Post by **MMamdouh** » Fri Dec 29, 2006 11:59 pm

you are quite right... basicly oil sludge is a big problem and for our engines it is indeed very critical for the hydraulic lifters.

i use engine flush with every oil change and i never use my oil over 5000k kms... now with BP visco every one is telling me to go up to 15k kms but i won't go that far all of a sudden, i went up to 7k last time and attempting to go up to 10k this time... last oil change gave very positive feedback about that oil and it showed it can survive more than 7k kms.

will keep you posted.

MMamdouh

Sinisha · Post by **Sinisha** » Mon Feb 12, 2007 8:52 am

There was no reliable way to "inspect" oil quality during oil change, excluding obvious signs such metal particles, water or fuel in oil. Oil is "dirty" after few hundreds km since is loaded with some aditives such a detergents which catch up most of carbon deposits in engine - oil turn to black. In engine with LPG oil stay light-collored for many kms. There is no "bad" oil nowdays, there is good oils and even better oils. But, the major differences is noticable in extreme conditions: cold start and overreving. In cold start oil have to flow in a second through entire engine to avoid dry friction, vhen overreving and overheating the oil film must be consistent and strong to achieve full protection. Engine could last for million km without wearings if they not turned off at all.

Turtle_Wax · Post by **Turtle_Wax** » Mon Feb 12, 2007 1:06 pm

The engine oil bible in this link is interesting read. Some other useful stuff there as well.
http://www.chris-longhurst.com/carbibles/