I just rebuilt my 1983 chevy 5.7 engine with omc drive. I know 30 wt is normal oil for it but 10-30w is best for break in oil. What do they used in new boat motors? Thanks for your help.
Re: Weight of oil to use in a rebuilt 350 inboard?
I'm not sure what they use new, but when I rebuilt my 302 last year, I used straight 30wt Castrol to start out with. Changed it at 1-2 hours, then again at 15.
