Oil change question

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Joew2604

Veteran Member
Joined
Apr 15, 2013
Messages
53
Location
USA
Vessel Name
Peterpan 111
Vessel Make
Gulfstar
Changing oil and filter on Universal diesel in Catalina 35. I have an unused gallon of O'Reillys 5-30 oil. Do you think it would be OK to use this or should I buy the Rotella T 10-40? Thanks for your thoughts.
 
Do what the manual or the sticker on the motor says...?
 
Diesel Engine Oil

Short answer - NO ! :eek:

You must use ONLY a diesel rated engine oil in a diesel Engine or major engine internal damage will occur. :thumb:

No exceptions. Unless you want to turn your diesel engine in to engine salad. :hide:

I don't know anything about the " gallon of O'Reillys 5-30 oil " oil & what it's specifications are, but it sounds like it is car gas engine oil.

That is a No-No to use gas engine oil in any Marine Diesel engine.

How about instead using some good old "Chevron Dello Diesel Engine oil" - Available almost every where & Diesel rated & not expensive. Even have it at Sam's club. I use either straight 30 weight or 40 weight in my Diesel.

Please, read the engine owners manual for the correct weight & Viscosity diesel engine oil that you are to use in your diesel. 5-30 oil is for good gas mileage in gas engine & not usually used in old technology design marine Diesel engines.

use the correct oil & you will be happy you did. :smitten:

Good luck.

Alfa Mike :thumb:
 
He dosn’t need luck now that he’s got the word.

“Salad”?
I wouldn’t have thought the penalty was quite that bad.
 
Save the O'Reilly's oil for your lawn mower. Get the owners manual out and see what the recommended oil weight and spec are for your engine. Once you find out that then you can select the brand that best meets your needs.
 
But on the other hand, if you don't need it for something else, hang onto it. Like my dad used to say, "in an emergency, any oil is better than no oil".
 
Short answer - NO ! :eek:

You must use ONLY a diesel rated engine oil in a diesel Engine or major engine internal damage will occur. :thumb:

No exceptions. Unless you want to turn your diesel engine in to engine salad. :hide:

I don't know anything about the " gallon of O'Reillys 5-30 oil " oil & what it's specifications are, but it sounds like it is car gas engine oil.

That is a No-No to use gas engine oil in any Marine Diesel engine.

How about instead using some good old "Chevron Dello Diesel Engine oil" - Available almost every where & Diesel rated & not expensive. Even have it at Sam's club. I use either straight 30 weight or 40 weight in my Diesel.

Please, read the engine owners manual for the correct weight & Viscosity diesel engine oil that you are to use in your diesel. 5-30 oil is for good gas mileage in gas engine & not usually used in old technology design marine Diesel engines.

use the correct oil & you will be happy you did. :smitten:

Good luck.

Alfa Mike :thumb:

Hi,

Good answers:thumb:

Only the manufacturer's approved oil rating diesel oil "API" and the viscose class e.g. W15-40. W = winter

NBs
 
I would only use diesel rated oil.
 
Save the O'Reilly's oil foro your lawn mower. Get the owners manual out and see what the recommended oil weight and spec are for your engine. Once you find out that then you can select the brand that best meets your needs.

O’Reilly’s oil may be re-branded Castrol like Valvoline re-labeled as NAPA oil.

But diesel engines need oil formulated for diesels.
 
Diesel oil is formulated different than gasser oil, but many are rated for both. Look at the API specs. C specs are for diesel, S are for gas. Second letter is the sequential spec. So if it says API CH/SG, it can be used in both.

A Universal sailboat aux is probably a Kubota base engine, which is well known for not being picky on oil. Could probably run on Wesson oil.

A new high output turbo diesel or new Corvette car is going to get exactly what they spec. An old Kubota is not so picky.
 
Ski has it right, READ the oil can.

And the engine maint manual "Da Book"

Older engines need less detergent than new engines so a rating of CD may be all that is required.

Oil contains about 20% non oil additives.

It is not good practice to mix brands as the interaction of the additives is unknown.

Modern high output turbo diesels need special oils mostly to help the exhaust system function for the air police.
 
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"But diesel engines need oil formulated for diesels."

The basic difference in oils is the additive package with most of the difference in the level of detergents required.

If the oil is API rated for your engine, its fine , weather its also works in gas engines.

All the newer diesel or gas car and truck engines that must eat their exhaust (EGR) need a higher grade of detergent than early engines that do not.

Using a "higher" grade oil than the mfg specks does nothing bit cost money.

Some folks believe that a single weight oil will have an engine last longer between rebuilds , (if OK by Da Book) than multi grade , but it could be just a tale.

If you want a "treat" for your engine , change the oil more often.
 
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Universal oil

5-30 is designed for gas engines in newer cars. it was developed to produce higher mileage and because internal parts of the engines require hydraulic actuation, ie, variable valve timing. The manual calls for 30 weight diesel oil, however, in the PNW I used 15/40 Delo for 20 + years in my 5432.
 
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