boat oil

[wolcott]

My stepfather has an old '94 bayliner with a 3.0 liter GM 4 cylinder in it. Most guys run the Mercruiser 25W-40 oil. The board I just joined seems almost hostile to the idea of using any other oil & filters. 1)It seems to me that I could run Shell Rotella in 15W-40 as well as mobil delvac or chevron delo 400 in that same viscosity. Any advice appreciated.

[doc47]

Rotella's as good as any.

[ShovelStrokeEd]

It's a motor isn't it?

 

Hint: Motors can't read nor do they look stuff up on the internet.

 

Any of the oils you mentioned will be fine in there. In fact, for marine use, where there is often some heavy load running, I would prefer one of the diesel specific oils to regular automotive stuff.

 

Rotella is what I use in my bike(s) and have never had an issue with it. Be aware, there are two kinds, one synthetic and one dino, to put it broadly. Either will be fine.

[Matts_12GS]

the oils are fine, however, since it's a bayliner I'd check the guns thread and find the closest owner of something very large caliber and very high rate of fire and perforate the hull from a safe distance so it can sink without issue...

 

They're good boats for what they're built to do. Enjoy it and stop worrying about the opinions of others on the web.

 

 

 

 

Except mine of course!

[jfremder]

I've been running Rotella 15W-40 in everything but the cars for years. (It occasionally get's down to -15°F here in WI, so Rotella's a little thick in winter for the cars)

 

Inboard boat, Water and air/oil cooled bikes, Mower, etc. Nothing has complained. Buy it by the case from Sam's Club.

[wolcott]

Thanks, guys. These damn boats are worse than cars and bikes to work on. I am gonna try to talk my 74-year-old stepdad into selling it, as it just sits there most of the year. Lots of special tools required once you get into the stern drive. I just found out that there is a rubber impeller in the sterndrive which is supposed to be changed every year. You can tear it apart, but supposedly it requires a special tool to fit a seal back in properly. I will try to get engine up to snuff and have him get rid of it. Since he's right on the river, perhaps a canoe will be better when the next hurricane comes.

[Matts_12GS]

sounds like my dad, he's got a boat he uses very little mostly because it's a hassle to get it in the water, out of the water, too hot, too windy, too rough...

 

He just feels that he has to have one so he can tell all the folks back in MI how nice it is in FL to live near the gulf and have a boat....

[4wheeldog]

It's a motor isn't it?

 

Hint: Motors can't read nor do they look stuff up on the internet.

 

Any of the oils you mentioned will be fine in there. In fact, for marine use, where there is often some heavy load running, I would prefer one of the diesel specific oils to regular automotive stuff.

 

Rotella is what I use in my bike(s) and have never had an issue with it. Be aware, there are two kinds, one synthetic and one dino, to put it broadly. Either will be fine.

 

The only exception I know of to this theory involves small aircraft engines. It seems that the zinc used in conventional automotive type oils attacks the bearings. Otherwise, I have never seen any evidence that automotive oils are incompatible with any gasoline internal combustion engines. And diesel oils have some of the best additive packages available. JMHO. YMMV.

[Rider1200RT]

Any oil that meets or exceeds the engine manufacturers specs can be used as long as it is the right weight oil. Use what ever you like. IMHO never in the 'hysteria' of the internet has oil been a hotter topic than almost anything else.... I had a (Mercury) mechanic tell me that the synthetic oil I am using in my 4 stroke outboard (Suzuki), was no good as it wasn't made for saltwater use. I just walked away wondering what other BS he would come up with next, and arguing with a fool is not wise..

[steveknapp]

Any oil that meets or exceeds the engine manufacturers specs can be used as long as it is the right weight oil.

 

Most boats I've been around specify their own oil. Which is where the internet questioning comes in.

 

Other than the high loads, boats tend to sit a lot, and they tend to sit in damp places. Then they run at high loads. The specified change intervals are pretty much once a season.

 

Not saying "doom will come to those who don't use XXX brand oil", just pointing out some differences in the operating parameters.

 

As far as being hard to work on, there are some tips/tricks that make it easy.

 

But at the top of that list is my rule "the day I can't afford to pay someone to maintain my boat FOR ME, is the day I sell the boat". YMMV on that of course.

 

These are my opinions only, not that of my employer etc etc etc...

 

[ProductUser]

I've worked on Four Winns for years, all I/O's; I'm also a certified OMC mechanic. As previously stated, these are just high performance engines; use whatever oil meets the manufactures specs.

 

Yes, like cars, motorcycles, there are a number of special tools that are needed, especially if you just want to pull the drive.

 

ProductUser

[Lone_RT_rider]

Other than the high loads, boats tend to sit a lot, and they tend to sit in damp places. Then they run at high loads. The specified change intervals are pretty much once a season.

 

This explains the initial viscosity of 25W on the first number of the 25W-40. One of the benefits to using 0W-20 in cars is that the initial viscosity number allows the oil to get to where it needs to quickly in all (i.e. cold) conditions. That quick flow ability unfortunately works with gravity to cause issues in boats that sit a long time. You want an oil that can't drop out of the valve-train as easily.

 

Makes sense I guess...hmmmmm....I think I need to make a trip to West Marine today.....

 

Shawn

 

P.S. Matt, your a boat snob....