37L oil

"Hi all,
I'm looking to

"Hi all,
I'm looking to do an oil change on my 3.7L. Is there any difference between an auto type and marine? That is, can I use a automotive filter? Which one fits?

Next, the Seloc manual I have says to use a straight 40 wt oil. Is that right? Just sounds plain strange."

The mercruiser oil filter part

The mercruiser oil filter part #: 35-866340Q03. It is a W-7 Oil Filter by GM. Merc. says 40 weight oil is what you should use in warm weather. In your engine I would use Merc. 25W40 wt. oil or Shell Rotella 15W40 wt. or Mobil One 20W50 wt.

Oil filters have been discussed here to the moon and back. There is a division among members as to using auto filters vs. marine rated filters. Since most filters are mfgd. by a few companies they can be very similar w/strong and weak points. You can't go wrong w/a Merc. filter and oil. Other filters will work but to what degree is up to your satisfaction. One respected member technician uses Hastings filters. Your choice.