We have an older Cummins 855 in one of the silage trucks on our farm. Had a great UOA last fall, put about 150 hours on it before we put it away and then this spring it had milky gray oil in it. Took a sample, drained and changed the oil and these are the results. Wondering what you think. The current numbers are to the right.
Iron 16...35
Chro 1....2
Ni 0....1
Lead 3....4
Copp 3....17
Al 2....1
Tin 1....2
Cad 0....1
Sil 3....34
Sod 3....307
Pot 4....621
Moly 158..231
Bor 39...139
Mag 729..974
Cal 1320.1468
Phos 944..1335
Zn 1095.1194
Water Vis 13.3_16.9
TBN 5.8__7.9
Ox 9____14
Nit 13___37
So, I have some issues with coolant in the oil. I'm going to drop the oil pan and pressurize the cooling system and look for drips but do you think the small spike in Copper could indicate a problem with the oil cooler letting coolant into the oil? Since I've had the coolant in the oil, I probably run the engine for less than an hour. Could the copper just be a wear metal caused by inadequate lubrication with all the coolant in the oil? The engine itself has fewer than 2000 hours on it after I did an out-of-frame overhaul on it. The oil cooler was replaced with a take-off oil cooler from a different engine at that time. Also, where could the high Silicon be coming from? Is that from the anti-freeze as well?
Iron 16...35
Chro 1....2
Ni 0....1
Lead 3....4
Copp 3....17
Al 2....1
Tin 1....2
Cad 0....1
Sil 3....34
Sod 3....307
Pot 4....621
Moly 158..231
Bor 39...139
Mag 729..974
Cal 1320.1468
Phos 944..1335
Zn 1095.1194
Water Vis 13.3_16.9
TBN 5.8__7.9
Ox 9____14
Nit 13___37
So, I have some issues with coolant in the oil. I'm going to drop the oil pan and pressurize the cooling system and look for drips but do you think the small spike in Copper could indicate a problem with the oil cooler letting coolant into the oil? Since I've had the coolant in the oil, I probably run the engine for less than an hour. Could the copper just be a wear metal caused by inadequate lubrication with all the coolant in the oil? The engine itself has fewer than 2000 hours on it after I did an out-of-frame overhaul on it. The oil cooler was replaced with a take-off oil cooler from a different engine at that time. Also, where could the high Silicon be coming from? Is that from the anti-freeze as well?
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