Inboard engine oil: Using automobile oil?

R

Ridley

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Comments about using top grade automobile oil in a marine inboard engine versus using marine oil? Do marine oils really protect better?
 
I had a friend who would use absolutely nothing but "SeaRay" branded oil in his Mercruisers that were installed in his SeaRay. Anal, totally anal.

All the oils I know of are rated by standards for spark ignition (gasoline engines) or compression ignition (diesels). There is no mention of marine or automotive.

By the way, SeaRay and all the rest of the machinery manufacturers are simply rebranding something made by the big boys in the oil business.
 
Valvoline. I buy it at Kragen auto by the case. I also buy Quaker State or Castrol, it depends on which is on sale. As long as it has the latest and greatest API service rating (SMSLSJSH) that's what I buy for the boat, the turbo car, the van and the pick-up.

I'm different with oil filters. Only WIX or Purolator. Same goes with with spark plugs on the boat because I'm in fresh water: Autolite.
 
This topic has been thoroughly discussed many times.
For the past 20+ years and 2 boats, I've used nothing but premium diesel-engine rated oils and never had an oil-related issue.
I currently run Shell Rotella-T 15W-40 in my Crusaders.

Uh, and I agree with yzer- NAPA Gold filters. Waaay better than those orange ones!
 
yzer has hit the target. No need to buy re-branded oils. Get any of the popular nationally advertised
oils that are nost available to you. The only "secret" is to ensure that you change the oil at least as
frequently as the engine manufacturer specifies.
 
yzer is absolutely right.

Autozone, Discount Auto Parts, NAPA, etc., are the best places to buy oil. Name brands, and the viscosity ratings that match your owners manual.
 
I smile at the mention of Kragens. I used to work at Store #1 on East Santa Clara Street when I was a kid. The cash register receipt said, "Al and Dave Kragen Thanks You". Who knew they would get so big.
 
They're being taken over by a larger company but I forgot the name.[:I]
 
I still own my 1985 Chris Craft Scorpion which is 24yrs old with a 350/260 mercruiser engine. I have only used Mercruiser 25w-40 and filter as recommended by the manufaturer and have not had any issues related to lubrication and breakdown. This engine has never had an issue. I have also used mercruiser 25w-40 on my Carver Montego with 454 blue water inboards and never had any issue related to lubrication or break down.

With my current boat I will only use what is recommended by the manufacturer, Volvo. I use 13 gls of Synthetic for my 480 Volvo's at $28.00/gl. Do the math, But I sleep good at night knowing I am using what is recommended.

Here is some info from Mercruiser on lubrication.

What type of oil should I use? Can I use synthetic oil?
Engine Oil

To help obtain optimum engine performance and to provide maximum protection, we strongly recommend the use of the following oils listed in the order of recommendation:

MerCruiser / Quicksilver Synthetic Blend, NMMA FC-W rated, 4 cycle oil.
MerCruiser / Quicksilver 25W40 NMMA FC-W rated oil.
A NMMA FC-W rated oil.
MerCruiser / Quicksilver 4-cycle 25W40, non FC-W rated oil.
A good grade straight weight detergent automotive oil per the operating chart below.
NOTE: The use of non-detergent oils, multi-viscosity oils (other than as specified), non-FC-W rated synthetic oils, low quality oils or oils that contain solid additives are specifically not recommended.

This crankcase oil recommendation supersedes all previously printed crankcase oil recommendations for MerCruiser gasoline engines. The reason for this change is to include the newer engine oils that are now available in the recommendation.

Older owner manuals, service manuals and other publications that are not regularly updated will not be revised to show this latest engine oil recommendation. Current owners manuals, service manuals and other service publications that receive regular updates will receive this revised recommendation the next time they are updated.

http://www.mercurymarine.com/serviceandwarranty/mercruiserfaqs/fueloil.php
 
"They're being taken over by a larger company but I forgot the name."

Yes, well about the fifth owner. When I was there, the family had just sold to Lucky Stores..remember them?
 
Using the manufacture's oils is fine as long as you do not mind paying for the extra cost. If switching to a different brand, just make sure it meets or exceeds what the engine manufacture specifies. I have never used Merc's oil and by engine is 17 years old without any issues. Marine engines are very similar to automotive engines. In fact they are derived from them. The difference is not really the engine, but how they are used. Cars run at 190* or higher versus a boat at 160*. A car just putts along versus a higher load on a marine engine. The good news is that most marine engines get an oil change way prior to it causing a problem.
 
as others have noted this issue has been vetted on many other threads. that said it is most important to read the specs from your specific eng mfg's. there are specific weights and industry ratings for oil and your owners manual will specify the reccomended weight and min oil ratings for your motor. if you follow those you will not go wrong.
 
There have been a lot of debates on which type and/or brand of oil to use in a marine engine. I believe we all will agree that marine engines are designed to operate in a totally different environment than auto engines and are subjected to higher operating loads. The two main issues a marine engine has to deal with are water intrusion and high RPM operation. With water circulating thru exhaust manifolds & risers the potential for water intrusion into the block is greater than it is for auto engines. I feel the most important thing to look for when selecting which oil to use is to look for the NMMA certification on the container. If it’s a 2-stroke engine (except for Seadoo) you should look for “NMMA TC-W3” and if it’s a 4-stroke engine you should look for “NMMA FC-W”. Oils produced to these standards cost more because of the testing that is required by NMMA for certification. One of the tests that FC-W requires for certification is a corrosion test. This is a test where a test coupon is cleaned & then coated with the oil being tested. The test coupon is then subjected to a salt fog spray for a set time and then cleaned and checked for corrosion. There are other tests that are required by NMMA in order for the oil to be certified for the higher loads that a marine engine may encounter during operation.

This doesn’t mean that other oils that don’t have these markings on the containers would not protect a marine engine in these extreme conditions. It just means that any oil that has these markings have been design, tested, and certified for marine application. You could go for years without any water intrusion and never know if the oil you use would stand up to the test of corrosion caused by water. I don’t under stand why anybody would take that chance when you consider the cost of our boats and boat repairs.
 
My boat is 28 years old and the original owners used Penzoil 30wt.
Both engines burn zero oil and run great.
 
quote:
Originally posted by MARINETECH

marine oil can have more water suspended in it than auto oil
that is it

Click to expand...


I do not believe that to be true. Please tell me where you read that by an engine manufacturer or oil company.

I do agree for marine gear oil or grease, but not for marine engine oil.
 
An engine in a boat is more of a constant RPM engine that a car. I would suggest diesel rated 15W40 oil or HDO 30W or Merc oil 25W50. You want something with a heavy duty additive package. There are also some great synthetic oils for marine engines. Cost should not be a big deal, you change it once or twice a year. And you boat cost how much??
 
quote:
Originally posted by MARINETECH

Factory training for Merc

Click to expand...


WDR that works great for sales; is there scientific data to quantify your statement.

FWIW, I do use Merc synthetic in my 6.2 Horizons because if there is an event whilst the engines are in warranty, I don't want any loophole for Merc to be able to climb through. After the warranty is over, it will be a synthetic that meets the Merc specs. Probably Rotella or Delo.
 
Do not use an auto grade multi-viscosity oils (i.e., 5w30, 10w30) in an inboard marine engine. The viscosity improvers in the auto oils will shear down quickly leaving you with the equivalent of a 20w oil. Also, the mild additive package in an auto oil cannot stand up to the higher levels of water and fuel dilution in a marine environment. Diesel (and "marine") oils are formulated with extra additives to deal with this. These oils are labeled with API service rating of CF or some derivative of that starting with a "C".
 
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