Re: Is 10W-30 or SAE 30 same & Itming for octane 91 gas
think of your motor as a generator rather than an automotive engine. unlike your car or truck which has a large transmission to keep your rpms to a minimum you boat basicly has two gears forward and reverse of which can only increase speed buy more rpms.
so your running down the lake for an hour at 3800 rpm, you need a good thick oil.
old spects 30 weight (detergent)
new spects 25/40
your choice, just dont mix them unless your in a pinch.
rob