What oil to safely dump in engine?

[mt_bulldawg]

I have a 1990 cruiser with Merc. 305 and Alpha outdrive. Just bought it a month ago - runs great and all, but last time out I noticed a little oil in the bilge when I drained. I checked oil level in engine and it could use a quart. Problem is I'm not sure what to dump in there - don't know what oil was being used and the service guy that did all this is on vacation. So is there something I could safely dump in for the the next month? It'll be winterized by first of Oct. with an oil change anyway. 10w-30? 40? Thanks in advance. RIck

 

[alexr254]

Re: What oil to safely dump in engine?

As per service manual for my engine which is a 1989 3.7l it says this:

The use of non-detergent oils, multi-ciscosity oils (other than 20w-40 or 20w-50), low quality oils or oils which contain solid addiditves specifically are not recomended.

Also dependant on the ambient temp
< 32F = SAE 20W, SF
32F to 50F = SAE 30W, SF
> 50F = 40W, SF

I am n o mechanic, just thought i would post what info i had on hand.

 

[Volphin]

Re: What oil to safely dump in engine?

As per service manual for my engine which is a 1989 3.7l it says this:

The use of non-detergent oils, multi-ciscosity oils (other than 20w-40 or 20w-50), low quality oils or oils which contain solid addiditves specifically are not recomended.

Also dependant on the ambient temp
< 32F = SAE 20W, SF
32F to 50F = SAE 30W, SF
> 50F = 40W, SF

I am n o mechanic, just thought i would post what info i had on hand.

And yet, Merc is now selling multi viscosity oils with detergent agents. Amazing. Any oil you would run in a Chevy of the same year is fine. Been running Castrol 5W/30 for 10 years with zero issues.

V

 

[Don S]

Re: What oil to safely dump in engine?

GUYS, He's not asking what type of oil to use, he wants to know what type to ADD to his low oil that he doesn't know what is. could be dino, could be synthetic. He doesn't know. That is his problem.

Personally, I would just change the oil and filter and choose the oil you want to use and always use it. If you have the shop change yor oil, get an extra quart so you know what they use, and keep it on the boat.