We have 4 each 50SG engines that have been in operation for about 1 1/2 years. The lead unit has logged just over 5000 hours, with the lag unit over 3000 hours. Run-times average 8-10 hours/start in daily peaking service.
Quarterly oil analysis is showing a rising trend in Aluminum content, with 2 units at or over 10 ppm. Oil is Mobil Pegasus 1005, and make-up rates have been well within spec.
We’re not aware of any aluminum components in these engines apart from the valve covers, crankcase covers, and similar non-wearing items. Has anyone else seen rising aluminum content in your oil analysis, and if so, what is the source?