What engine oil should I use

[Black as]

Hi guys
I have imported into Australia a 1988 Bayliner with a 350 chev 4 barrel with a Cobra drive set up, I am currently doing a complete service of the engine and doing everything by the book. The only thing that Ive found in the book that's a little confusing is the engine oil type.

Is there a specific oil I should be using as the manual states not to use everyday automotive oil and also states temperatures.

I normally use my boat in the summer season only and temperatures over here vary from around 17 deg Celsius to up to 45 deg Celsius, but then again you wouldn't find me out in my boat at when it hits 45

From the experience you guys have had can you please recommend the best oil?

 

[Gary H NC]

Re: What engine oil should I use

Straight 30 weight oil. Do they sell Rotella or Delvac oil there? It is used in diesel trucks and works just fine in the marine engines.

 

[Black as]

Re: What engine oil should I use

Straight 30 weight oil. Do they sell Rotella or Delvac oil there? It is used in diesel trucks and works just fine in the marine engines.

Ive never herd of those oils, but I have done a lot of reading about oil types and its a bit all over the place. I need peace of mind that what ever oil I use is the right oil.

 

[Lou C]

Re: What engine oil should I use

Chevron Delo 400 straight 30 is what I use in my OMC 4.3
You can also use Shell Rotella straight 30
Or Pennzoil Marine HD straight 30

 

[Black as]

Re: What engine oil should I use

Chevron Delo 400 straight 30 is what I use in my OMC 4.3
You can also use Shell Rotella straight 30
Or Pennzoil Marine HD straight 30

Can you advise why you use a straight 30 W

I rang a marine service center this morning and they said use a 25w40 and said any brand would be o.k and then I asked whats the best oil and they said Quicksilver. Im not an any oil will do type of person, I just want the right one and feel safe that my engine is well maintained. The current brands of oils you guys mention are not familiar over here

 

[Fishermark]

Re: What engine oil should I use

I need peace of mind that what ever oil I use is the right oil.

Peace of mind will be the last thing you will get by asking a question like that here. The good news? You will get every imaginable answer possible, so you can take your pick! (Do a search of oil threads and you will see what I mean).

 

[Rocky_Road]

Re: What engine oil should I use

Just in case you haven't seen the latest Mercruiser oil recommendations, here it is:

There isn't any greater "peace of mind" then using what the engine manufacturer tells you to use...period.

 

[180shabah]

Re: What engine oil should I use

...and before the OMC vs Merc argument comes up, they both used the same GM base engine, so the same oils work in both applications. FWIW - a marine oil will deal better with moisture, but you have to decide if that is a concern for you.

 

[Don S]

Re: What engine oil should I use

Marine oil specs and what the oils are required to do has nothing do do with moisture.
Marine engines run completely different load factors.
How often do you run a car at 4000 rpm, up a steep hill, in first gear, for hours on end?
That is how a boat engine feels.
A single grade oil, or a specifically designed oil for marine engines supposedly lasts longer than a multigrade automotive oil.
But, I have never seen an engine failure due to type of oil used.
Change the oil yearly or every 100 hrs (whichever comes first), as recommended and use whatever oil and filter you want and you should be fine.

 

[Black as]

Re: What engine oil should I use

Marine oil specs and what the oils are required to do has nothing do do with moisture.
Marine engines run completely different load factors.
How often do you run a car at 4000 rpm, up a steep hill, in first gear, for hours on end?
That is how a boat engine feels.
A single grade oil, or a specifically designed oil for marine engines supposedly lasts longer than a multigrade automotive oil.
But, I have never seen an engine failure due to type of oil used.
Change the oil yearly or every 100 hrs (whichever comes first), as recommended and use whatever oil and filter you want and you should be fine.

Thanks Don, so in our Australian climate would the Quicksilver 25W40 be a good choice?

 

[Don S]

Re: What engine oil should I use

The Merc 25W40 would be good in any climate. Look at the Merc chart in Rocky Road's post.