Wrong engine oil!

Nov 16, 2012
1,037
Catalina 310, 2000, #31 31 Santa Cruz
Changed the engine oil and filter today (25XPB, 2200+ hours). Getting easier to do. While writing up what I did I suddenly realizes that I had put gasoline engine oil (5-30) in, rather than diesel oil (10-40). I'm hoping that all I need to do is change it (again), this time with the correct oil. Any other issues? Any point in changing it twice?
 
May 12, 2004
1,502
Hunter Cherubini 30 New Port Richey
For your piece of mind, just change it then quit fretting over it. Life's too short to sweat the small stuff.
 
Oct 22, 2014
20,992
CAL 35 Cruiser #21 moored EVERETT WA
Rob it is not a catastrophe... It will be great for winter time. You might consider change before next mid summer. On the other hand you be on the Pacific ocean in Northern Cal. You should be ok...

What Is the Difference in 10w-40 Car Oil and 5w-30 Oil?

by Harry Havemeyer
Motor oil provides the necessary lubrication for an engine's moving parts. The oil acts as a lubricant that allows the pistons to move in the engine block without creating excess wear. The Society of Automotive Engineers, or SAE, classifies oil by viscosity and engine manufacturers provide a recommended motor oil viscosity for use in a particular engine. Mileage and weather can dictate adjustments in the proper viscosity of motor oil used in an engine. The difference between 10w-40 and 5w-30 motor oil is in the ability of the oil to cling to the engine's moving parts, which dictates the best application for each type of oil.
First Number
The first number in the motor oil's name describes the oil's cold viscosity. Cold viscosity refers to the thickness of the oil upon a cold start of the engine, before the pistons and engine block have warmed up from ignition and combustion. Motor oil's cold viscosity is important because it dictates the lubrication during the hardest part of the combustion cycle, the startup and initial ignition in gasoline engines or combustion in diesel-fueled engines. A 10w-40 motor oil is a thicker oil at startup than a 5w-30 motor oil. Therefore, 10w-40 oil clings to the engine's moving parts more than the lower viscosity 5w-30 oil.
Second Number
The second number in the motor oil's name describes the viscosity of the oil when the engine is warm and the oil reaches operating temperature. This warm viscosity is always going to be heavier because the engine requires a higher viscosity oil to provide ample lubrication through the broad range of the engine cycle and temperatures. The 10w-40 motor oil clings to the engine's moving parts more than a 5w-30 motor oil does at higher temperatures; this means the 10w-40 is the thicker of the motor oils when the engine is running.
 
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Mar 20, 2004
1,729
Hunter 356 and 216 Portland, ME
diesel oil has a different additive package from gas engine oil and is blended to better match the characteristics of the diesel. change it (once) and then forget about it
 
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Nov 6, 2006
9,884
Hunter 34 Mandeville Louisiana
As Chuck says, diesel oil has different additives to control blowby products (a diesel engine generally has more blowby than a gasoline engine) and to hold gunk in suspension until it can be purged. There is no rush to change out the 5W30 but sometime in the next 10-20 hours would be fine. No need to double change..
 

jviss

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Feb 5, 2004
6,745
Tartan 3800 20 Westport, MA
The weight is not so much a gas v. diesel thing, as is the additive package. For gas, look for service specs starting with the letter "S," for diesel, "C."

This, from the Westerbeke (Universal) website:

What type of oil should I use in my Westerbeke or Universal engine/generator?
Use a well-known brand and try to use the same brand each time you change the oil. Avoid mixing brands of oil. Different manufacturers use different additives, and mixing brands may cause a problem if additives are not compatible. More important is to use the correct A.P.I. (American Petroleum Institute) and S.A.E. (Society of Automotive Engineers) ratings. For Westerbeke and Universal DIESEL models use A.P.I. code CF or CG-4, S.A.E. #30, 15W-40, 10W-30 or 5W-40. For Westerbeke GASOLINE models, use A.P.I. code SJ, S.A.E. #30, 15W-40, 10W-30 or 5W-40.
 
Nov 16, 2012
1,037
Catalina 310, 2000, #31 31 Santa Cruz
Thanks. I figured the additives were an issue. I wasn’t too worried about the viscosity difference. Sounds like an easy screw up to recover from.
 

jviss

.
Feb 5, 2004
6,745
Tartan 3800 20 Westport, MA
Thanks. I figured the additives were an issue. I wasn’t too worried about the viscosity difference. Sounds like an easy screw up to recover from.
I wouldn't even be concerned about running it for a season, and then going with "diesel oil" next time.

Are you planning on trashing the new filter, too, of you change it?
 
May 24, 2004
7,129
CC 30 South Florida
A film of oil prevents metal to metal contact between moving components, mainly between crankshaft and bearings and piston rings and cylinder walls. The tolerance to what the components were designed and manufactured dictates the necessary oil viscosity. 5W-30 is a little thin for the Diesel engine specifications and could likely result in oil burning, a slightly elevated running temperature and low oil pressure. Go ahead and change the oil and I would recommend a grade of 15W-40. Any small amount of oil left in the crankcase will be diluted into the thicker oil. I would not worry about having done any damage or that any residue would inflict any in the future. I once had a ruptured lift pump diaphragm which leaked diesel fuel into the crankcase and the result was an oil so thin that made 5w-30 seem like molasses. I first heard an unfamiliar clatter in the valve train which led me to check the oil level which was really high and rubbing the oil between thumb and forefinger confirmed it had lost most of viscosity. Long story short replaced the pump and changed the oil with seemingly no lasting ill effects. Another thing that can degrade viscosity is excessive heat; any time the engine overheats it is recommended that the oil be changed. Your mistake was not that serious.
 
Jan 5, 2017
2,263
Beneteau First 38 Lyall Harbour Saturna Island
Diesel generally has more E.P. additive for the higher compression engines i was told. I would change the oil before running it if it were mine. Save the worry.
 
Nov 16, 2012
1,037
Catalina 310, 2000, #31 31 Santa Cruz
I wouldn't even be concerned about running it for a season, and then going with "diesel oil" next time.

Are you planning on trashing the new filter, too, of you change it?
Filters are relatively cheap. I've always changed filters and oil at the same time, car or boat.
 
Feb 14, 2014
7,399
Hunter 430 Waveland, MS
I figured the additives were an issue
I have been using a synthetic Oil for 2 seasons. Last I researched the differences, the "C" rating is now "J" only because of the contaminant removal for diesel rigs that run the highways.

It has to do with lowering the Sulfur content of refined diesel oils.
You can actually blend your own range of so called "weights" of Lube Oils.

I use 5 quarts of this...
https://www.samsclub.com/sams/mobil-1-5w-30-motor-oil-6-1-qt-bottles/159902.ip?xid=plp:product:1:1
and 1 quart of this...
http://rotella.shell.com/products/rotella-triple-protection.html

To cover the recommended Viscosity Range of my Volvo Penta 50 hp, at my warm water operating temperatures along the Gulf. [mine starts faster than my Ford Expedition gas engine]

With the synthetic, I have reduced Carbonization as proven by my used oil color and cold start smoking.
_____
As to refined diesel oils...
Oil Sulfur content for engine longevity has not been shown to be a factor.
Jim...
 
Feb 26, 2004
22,759
Catalina 34 224 Maple Bay, BC, Canada
While writing up what I did I suddenly realizes that I had...
Rob, remarkably consistent responses. I think you've set a record for the forum!
Now...care to share just HOW you did this???:):):)
 
Oct 22, 2014
20,992
CAL 35 Cruiser #21 moored EVERETT WA
So you young guns with your turbos and shiny new Beta/beake/saildrive/Yama jammers it seems easy to read the newly minted manual and get the engineering wisdom to buy the current knowledge about oil for your diesel.

What are your ideas regarding an old 1973 work horse, built like a timex watch. It takes a licking and keeps on ticking. The design was to fuel with diesel based on the 1940’s standards. Sulfur was a prime ingredient, and oil came standard weight.
Where the manual says
0-30F 10W. 30-80F 20W. and Over 80F 30W
From companies like. A. Duckham Co Ltd and Total Oil Co Ltd. which featured “Total Super Universal Tractor Oil (Multagri TM)”
Which unfortunately is not among the brands featured at the local WM or Marine Chandler.

What’s a hip young boat owner to do?
 
Apr 8, 2010
1,942
Ericson Yachts Olson 34 28400 Portland OR
So you young guns with your turbos and shiny new Beta/beake/saildrive/Yama jammers it seems easy to read the newly minted manual and get the engineering wisdom to buy the current knowledge about oil for your diesel.

What are your ideas regarding an old 1973 work horse, built like a timex watch. It takes a licking and keeps on ticking. The design was to fuel with diesel based on the 1940’s standards. Sulfur was a prime ingredient, and oil came standard weight.
Where the manual says
0-30F 10W. 30-80F 20W. and Over 80F 30W
From companies like. A. Duckham Co Ltd and Total Oil Co Ltd. which featured “Total Super Universal Tractor Oil (Multagri TM)”
Which unfortunately is not among the brands featured at the local WM or Marine Chandler.

What’s a hip young boat owner to do?
Well, don't be defensive about your older diesel, for starters! :)
Or, are you just trying to wind us up. (LOL)

It's older than my engine, but they are more similar than they are different.

I know of a diesel mechanic with 40+ years of experience and he advises that when my engine was built the engineers specified the oil that was being formulated at the time. Decades later there are different and better products on the market. So I use Delo 400, 15-40 weight. My historic original engine manual specifies 30 weight for my 1988 engine, and that was and is fine. But things change.

Shop around, too. West Marine is handy when you need something on short notice, but you can usually fine oil quite a bit cheaper elsewhere. Also, WM is slowly backing out of the chandlery business.... few more years and the transition to clothing, fishing gear, and SUP stuff will be complete! :(

Fair winds.
 
Feb 14, 2014
7,399
Hunter 430 Waveland, MS
Where the manual says
0-30F 10W. 30-80F 20W. and Over 80F 30W
Remember those are COLD START temperatures.

My engine cooling runs at 180°F after the thermostat kicks in. Even in cold weather, here on Gulf, where the cooling water is seldom below 60°F, even in the rivers.

Here, according to those above numbers, I want 20W! Forget the Multi Range oils.:clap:

BTW, I don't blend for my 16hp Yanmar genset diesel.
Jim...

PS: I just read the Shell Rotella synthetic specs. They claim better Oil aeration. Say What?:confused: