My boss just gave me a few un-opened 1 liter bottles of Castrol SAE 30 non-detergent oil today. He was going to throw them out since he has no need for them as he bought them in error back a few years ago. He asked if I wanted them and I said sure, why not. I was wondering if it would be ok to use in an old Briggs push mower for short OCI's due to not having any detergent?