Black Oil after 500 miles?

[DKasper]

Hi Guys,

I brought home a '93 W350 this weekend, and I have a question about how long the oil stays clean after a change. On my '93D350, the oils stays pretty clear for about 1500 - 2000 miles. I change it between 3k - 4k miles.



On this new truck, the previous owner said that the oil turns dark after about 500 miles. The truck is pretty much stock, though I believe the pump has been tweaked a little bit - idle is a bit high and has a little more "snap" than most stockers.



Do you think the rapid oil color change is something I should be concerned about? What would cause that to happen -- soot?



Thanks for your thoughts!



Dave

'93 D350

'93 W350

 

[Greenleaf]

Does this truck smoke? The engines in my bus fleet have black oil soon after a change. My truck seems to have a cleaner looking oil for quite some time after a change, however this may not be the case now that it has an abundant amount of mods. Heavier fueling, more soot.



What kind of oil was the previous owner using?



Scott

 

[DKasper]

Hi Scott,

Good thought on the smoke. There is just a little puff of smoke on startup, but I've seen no more than that. I even had him drive around town while I followed him to watch for significant smoke -- didn't see anything other than a light haze under heavier throttle.



Previous owner was using Shell Rotella -- I've been using Delo 400 and will switch this one over tonight.



Thanks

Dave

 

[Greenleaf]

I was hoping you'd say something else,but that is the same oil my fleet uses Three things; change out the oil to you'r preferred brand,change the air filter,take an oil sample and adjust valves. OK, that's four. Also look at timing adjustment and see if you can locate any slime/goopy substance under the valve covers. Should be nice & oily w/out said gunk. That'll keep ya busy awhile.



Scott

 

[RGT]

I am running Shell Rotella and have no prblems with it turning black, It gets a dark, but even at my last oil change 10k miles it was still pretty good looking, much better than what I change out of my 240D Mercedes at 5k miles, or much better than what I used to take out of some Detroit gensets at 200 hrs(Shell HD 30w), we tested their oil at every change and were always told to extend drain, the oil looked blacker than coal though, we once kept extending drain by 50 hrs and retested the oil and got out to around 500 hrs and were still being told to extend drain, but when we considred how much makeup oil we were adding between 250 and 500 hrs we might as well have changed it... so we settled on 200(250?) hr oil changes. 10k miles at 50 mph works out to 200 hrs, I add about 2 qts of makeup oil during this interval. I ran Castrol Enduron for one cycle, 14k miles and it stayed really clear out to around 6k miles added about 4 qts of makeup during that interval, I plan on keeping the Rotella and doing the 10k intervals from now on.

 

[Greenleaf]

MILES TO OIL CHANGE

I ran an ISB last school year a bit over 16K before they said to pull the plug. Most get changed out about 8 to 10K if they need it or not. Manual says 250hrs for 12valves and 500hrs for 24valver. I exceed that but, keep an eye on sample results.



I'll post some result no. s when I get a chance to do so.



Scott



Detroit Diesel Two-Strokes seem to have the blackest oil I have ever seen.

 

[DKasper]

Thanks for the ideas & input -- I think the best thing I can do is just get some samples checked and go from there.

More than anything I'm just wondering what is it that makes it black? Soot? From what? Timing off perhaps? Or maybe the engine just isn't as tight as others?



Hmm... .



Thanks!



Dave