4 stroke oil change question

[hertel11]

Just changed the engine oil on my 2007 4 stroke 9.9hp Johnson. Evinrude/Johnson Ultra 4-stroke synthetic blend oil is recommended and that is what I used but I am just a little below full, maybe just a couple ounces shy. Will it be ok to top off with a synthetic oil such as Pennzoil 10w-30? A marine mechanic at a local marina said he uses full synthetic Pennzoil 10w-30 in all his 4-strokes but I just wanted to check with you guys before I added it in. Thanks

 

[Crosbyman]

why not buy the same and keep the rest for next year's oil change

 

[hertel11]

Yeah. I will do that, it is just not available locally so I have to wait for shipping and I'm anxious to get on the water.