Got a 1971 350. Looks like the heads were redone and compression is good with the odometer reading 89K. Changed the oil and now 1K later it's black! First oil change was done with regular oil. Have both the Vavoline max life 50/50 blend and full synthetic on hand. Any opinions or ideas. Never seen oil go bad so fast!
I wouldnt worry about it. Some oils turn black sooner than others. all oils will eventually turn black. It doesnt nessesarily mean the oil is "dirty".
Many years ago an old timer mechanic told me that if the oil got black in short order, then it was doing its job. If it didn't, then all that dirt and crud was just sitting, waiting for the perfect opportunity to grenade your engine.:eek2:
it was probably black the next day but you only noticed 1k later if you want it to be good and clean change it several times in one day running 20-30 min in between changes (only one filter change needed) till it comes out good and clean then keep up on a good 3k changing schedule. Even a diesel can have clean oil at its oil change is serviced regularly and not allowed to get overly dirty I do this to my vehicles occasionally just to keep things nice inside
Id say it also depends on how clean inside the engine is. Only take a bit of old oil sticking around to dirty the new oil. In our Subaru the oil is nasty back again soon as you change it. Though in my Buick and Firebird it changes color much slower. If your worried, you can buy a bunch of cheap oil and flush the engine with the aid of some chemicals. Seafoam is a good one, A quart of ATF, quart of diesel, Rinsol and many others. Though its not gonna do much but make the oil look nicer longer, but it doesn't mean its working any better.
My oil stays clean longer now, because after a few months of frequent modifications it got oil changes every 400-500 miles. :laugh: Squeaky clean inside.
do an oil analysis. We use Blackstone Labs for $32.00 they will tell you everything about your oil including how much life it has left in it, (called a TBN). A perfect way to see if you have contaminates and catch problems before is to late. They will send you a free kit just look them up on the web.
