Monograde Engine Oils

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See the Cox Engineering - Oil for Yacht Eng's article on the (highlighting my addition)

BACCHUS Nautical Links Page

It's the best article for marine applications I've seen. SO many others are relative to OTR use with emission controlled engines.
I prefer the single wt oils but boat only in summer season so no cold start concerns. Looks like you are in a different location / situation. I'd follow eng mfg recommendations. I have noted Yanmar updated API specs recommended from what was published when my boat was new so I go with the updated recommendations.
I try to avoid the latest multi-grade API rating oils that are designed for OTR as mentioned above.
 
Lou, if 15-40 is a mfr. approved oil, why not use it. Lots of engines do, and it`s readily available.

Only one reason Bruce.
One quart of straight weight oil has more oil in it than multi-vis.
Oil is what lubricates your engine parts.
You don’t need mv oil in your boat engine unless it’s a fireboat.
 
I have CAT 3116 diesels--vintage 1994. The manual specifies single viscosity 30wt or 40wt, and explains briefly that the multi-viscosity oils have undesireable additives for this motor.

Yes,
If you don’t need them or wouldn’t benefit from then use straight wt oil. I’ll bet engine manufacturers of stationary engines that don’t need to work while not warmed up use straight wt. oil. I worked in a powerhouse in Alaska w a 1400hp engine (main) that had a 300 gal pump sump. Delo 30wt. And a warm up of 24 hrs. That is the lube oil and coolant was heated and circulated throughout the engine for 24hrs before startup.
Our trawler engines operate and start in mild temps. Also most all warm up slowly and have no need for mv oil.
Some think the lower viscosity of mv oil when initially started benifits from the flow capabilities. I do not.
 
The question earlier about the engine's age is an important one. Oils have evolved quite a bit over the decades, and each new oil standard (API rating) is backwards compatible with previous standards. So in general, a modern 10W-30 oil is a suitable replacement for any straight weight oil from 10W to 30W. There are exceptions, but they are just that - exceptions.


And related to this, I have to wonder.... We get all worked up over what type of oil to use. Brand, weight, multi vs straight, etc. It's as bad as filter micron ratings and anchors. So I have to ask. Has anyone, at any time in their life, of the dozens and dozens of motors we have all owned over the years in various vehicles and machines, ever had one fail because they used incompatible oil?


Personally, I have never had a failure, or even heard of a failure that traces back to the wrong oil selection. And strictly my opinion - I think fretting over oil selection is one of the biggest non-issues in the world of engines. I think any reputable brand meeting an industry specification called for in your manual, or backwards compatible with your manual, is just fine. Then start the engine, and use it.


:thumb:
 
Twistedtree & Todd 727

"Personally, I have never had a failure, or even heard of a failure that traces back to the wrong oil selection. And strictly my opinion - I think fretting over oil selection is one of the biggest non-issues in the world of engines. I think any reputable brand meeting an industry specification called for in your manual, or backwards compatible with your manual, is just fine. Then start the engine, and use it."

Read through the linked Cox Eng - Oil for Yacht Eng's.

Anecdotal example of modern oil attributed at least as a partial cause of engine problems and substantiated by Yanmar & Shell.

Many / most of the oil reports available are not specific to boats - this one is and I tend to put more faith in it than the trucker type analysis / comparisons.
I have very a different opinion re the oil I use in my motorhome Cummins engine.


I realize everyone is entitled to their own opinion and conslusion.
My effort is to get what I feel is good info in front of others so they can make their own educated decisions.
 
This is a bit like discussing anchors:rofl:.
Since oil was first used for lubrication, I believe there have been advances in formulation of lube oils.
Which is why I use multigrade oil.
 
This is a bit like discussing anchors:rofl:.
Since oil was first used for lubrication, I believe there have been advances in formulation of lube oils.
Which is why I use multigrade oil.
What grade do you use to lubricate your anchor? :)

L
 
What grade do you use to lubricate your anchor? :)

L
No moving parts in a Sarca :D. Unlike a plough.

Does anyone lube the hinge on a plough? It`s certainly possible.
There are people who love ploughs, danforths, etc and will have nothing else, lubed hinge or not. And others who think anchor design has moved on and improved on older designs. Some of each group regards the other as heretic.
 
Every night I rub my anchor in oil, I sing her a song, and we have a lovely night so I can sleep well while she works hard :)

I think I need a therapy lol

L
 
The question is about the suitability of mono-grade engine lube oil for trawler type boats. Having nothing to do w outboards I assume.

In the typical environments trawler engines work they start up at temps seldom (almost never) below 40 degress f. The typical lube oils flows very well enough to lube an engine at startup with mono-grade 30 or 40wt oil.
MV oils were developed for cars to be able to start at temps below 0 degrees f. I had a 1950 Plymouth that started dependably at 5 degrees below 0 .. with 30 wt oil. And this was w a 6 volt electrical system. This shows that a boat in a heated compartment should easily .. EASILY start at 40 degrees f. The notion it needs a mv oil is almost ridiculous. Clearly not needed .... IMO.
 
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I have CAT 3116 diesels--vintage 1994. The manual specifies single viscosity 30wt or 40wt, and explains briefly that the multi-viscosity oils have undesireable additives for this motor.

Some of the 3116 and/or 3126 engines had HEUI injection systems. I don't know which ones. HEUI uses engine oil as hydraulic fluid to power the injectors. An additional oil system pumps the engine oil to very high pressure, thousands of PSI.

If you have HEUI injection be very particular about your oil selection. Use only the recommended oils.

It is a very good engine but some oil doesn't do the job as required.

Aeration in the oil is an issue and oil with durable anti-foaming properties is required.
 
Every night I rub my anchor in oil, I sing her a song, and we have a lovely night so I can sleep well while she works hard :)

I think I need a therapy lol

L

Just as I thought, Mazola. Intervention group convening.
 
Every night I rub my anchor in oil, I sing her a song, and we have a lovely night so I can sleep well while she works hard :)

I think I need a therapy lol

L
I can think of several alternative way better sites to apply lube.:):):)
 
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