I have done oil testing through Blackstone since I have owned my Cub. With my latest oil test I had a spike in chrome (chromed cylinders) and aluminum. Mechanic checked compressions and they were 73-78 cold. I have not had to add more oil than normal. Also borescoped each cylinder and all looked fine except no. 1 had the corrosion shown in the photo. That was also there when he scoped it at annual in December. But this is the first oil test since last summer.
Chrome in testing had been averaging 14 but on this test is was over 500.
Any experience with best way to deal with this? Should I just get the cylinder repaired? Or continue to monitor the corrosion and see if it returns to normal at oil test in another 10hrs? Or some other approach?
As an aside, Blackstone always provides an informative personalized write up for each oil test. In this case they called me and warned me of the chrome spike. I am really pleased with their service.
Chrome in testing had been averaging 14 but on this test is was over 500.
Any experience with best way to deal with this? Should I just get the cylinder repaired? Or continue to monitor the corrosion and see if it returns to normal at oil test in another 10hrs? Or some other approach?
As an aside, Blackstone always provides an informative personalized write up for each oil test. In this case they called me and warned me of the chrome spike. I am really pleased with their service.