What kind of oil ?

[MORNING LIGHT]

Bought a Catalina 28 MK II 1996. Oil recommanded is 30 HD. Is there any benefit to switch to synthetic oil or it is not worth it since the engine just work during summer or at least warm weather? The engine is Universal
XP 25.

 

[Don S/V ILLusion]

Opinions vary but people I consider experts have told me it isn't a good idea to replace oil with synthetic in an older engine. What is important is to change it in the Fall before your winter lay-up.
Someone more knowledgeable than me can advise you on whether your single weight oil is non-detergent and if so, you should probably not use it. Who recommended 30 weight?

 

[Stu Jackson]

Here's one of tons of discussions about this:

http://forums.catalina.sailboatowners.com/showthread.php?p=1138715&highlight=rotella

I used "Rotella" for the search. You could also try others phrases, like engine oil, 15W 40, etc.

Your boat, your choice.

Engines 101 - The BIGGEST & BEST collection of M25 Series Universal Engine Information on the Internet, plus some M35, too

http://www.c34.org/wiki/index.php?title=Diesel_Engine

 

[MORNING LIGHT]

Opinions vary but people I consider experts have told me it isn't a good idea to replace oil with synthetic in an older engine. What is important is to change it in the Fall before your winter lay-up.
Someone more knowledgeable than me can advise you on whether your single weight oil is non-detergent and if so, you should probably not use it. Who recommended 30 weight?

As a matter of fact, I change the oil every fall and spring. The Universal owner manual indicates that you can use SAE 30 HD or 10 W40 but since this is a 1996, there has been a big evolution in oil manufacturing since then
and synthetic oil got better than ever.

 

[Marc Robic]

Hello Morning Light, just to let you know I will definitely switching to synthetic oil come spring. Your right about lubrication technology. It has greatly improved.