Engine oil shelf life?

[Ocean Sky]

On my recently purchased boat I have found 4x5 litres of unopened sealed Shell Helix Plus 15w40 Diesel.

There is no sell by date on them,i think they might well be 6 or more years old,as we have found quite a few things from that era..(ketchup etc!)

I am planning to do filter/oil changes etc.

Do you think it would be ok to use in my two Yanmar 3jh4e 40hp engines (2008) which have only ca200 hours on them?

Thanks for any suggestions.

[StuM]

General guidelines for shelf life of motor oil is 3-5 years for non-synthetic oil, 5+ for synthetics. But that assumes appropriate storage conditions. If it's been shaking around in a boat and subject to varying temperatures for more than 5 years, I wouldn't use it without getting a sample tested first. (A sample test is not expensive).

[Ocean Sky]

Ok many thanks for the information,it is semi synthetic i believe,it has been in the tropics all this time 24-35c .

I will try to get a test done.