Marine grade oil and filter

[bpmcl00]

Good day!

i just wanted to get some opinions on whether marine grade engine oil and filter is necessary.

or maybe marine filter and regular auto oil or vice versa auto filter and marine oil

Also what grade oil??

i live in GA and it gets pretty hot down here. i was thinking 25w-40 or just straight 30 weight?

still a little confused-

thanks

 

[mthieme]

Re: Marine grade oil and filter

I use regular auto filters and 30HD in my 4.3.

The water separator is marine though. My marine mechanic saw noticed it said I was one of the few people who don't use an auto oil filter for that purpose.

 

[bpmcl00]

Re: Marine grade oil and filter

your talking about the water seperating fuel filter correct?

 

[mthieme]

Re: Marine grade oil and filter

your talking about the water seperating fuel filter correct?

Right.

Regular auto stuff for the oil filter though.
The only problem you would run into is the filter rusting through.
Hopefully you change it often enough where this wouldn't be an problem.

 

[bpmcl00]

Re: Marine grade oil and filter

No since i live in GA and it gets pretty hot here should i run a 30w 40w or 20-50 or a 25-40
or either one will work

 

[JustJason]

Re: Marine grade oil and filter

they will all be fine.... but if you do extended hi rpm runs then 30 weight may be a little thin. 25-40 is mercruisers spec... and you can't go wrong with what merc say.
The only problem is merc is the only one who makes 25-40.
Use a high quality 20-40W from a brand name manufactorer (not wally world stuff)

 

[bpmcl00]

Re: Marine grade oil and filter

Thanks Captian!

So a quality 20w 40 is what it shall be.

Also i read that synthetic is not a good idea....

Thoughts on that?

 

[Don S]

Re: Marine grade oil and filter

 

[bpmcl00]

Re: Marine grade oil and filter

HAHA Don s to save the day again.

BUT. i live in GA it gets pretty hot here so should i run 40 weight???

 

[xxxflhrci]

Re: Marine grade oil and filter

Does your valve cover have a label on it that has tune-up and service specs? My Mercruiser does. It calls for 30 wt. So by reading that chart the Don S posted, I am supposed to ignore that label and go by the updated info, correct?

 

[bpmcl00]

Re: Marine grade oil and filter

mine doesnt

 

[69seabreeze]

Re: Marine grade oil and filter

Based on that chart, you are fine running the boat with 40wt as long as it doesn't go below 50 degrees. I would run that over the marine grade stuff for the cost advantage. If you get a quality auto oil that is SAE certified and SM rated then you should be fine. I don't know how cold it gets in Georgia but if you want to go out a lot when it's below 50 degrees just put in 30wt for the winter. I'm no expert on boats but I do the same sort of thing in my truck. Run 30wt all summer and 10w-30 in winter.

 

[bomar76]

Re: Marine grade oil and filter

Does your valve cover have a label on it that has tune-up and service specs? My Mercruiser does. It calls for 30 wt. So by reading that chart the Don S posted, I am supposed to ignore that label and go by the updated info, correct?

It's kinda hard for Merc to find every boat engine and outdrive they sold and stop by to change the stickers on the engines.
In lieu of this, they issue Service Bulletins that contain the updated data.
Go by the Service Bulletin.

 

[xxxflhrci]

Re: Marine grade oil and filter

It's kinda hard for Merc to find every boat engine and outdrive they sold and stop by to change the stickers on the engines.
In lieu of this, they issue Service Bulletins that contain the updated data.
Go by the Service Bulletin.

I don't expect them to stop by and change my sticker.

I also don't think I'm gonna change weights, either. It's been running fine on the same brand and weight for 23 years. I don't see a reason to change up now.

 

[45Auto]

Re: Marine grade oil and filter

i just wanted to get some opinions on whether marine grade engine oil and filter is necessary.

or maybe marine filter and regular auto oil or vice versa auto filter and marine oil

No particular oil or filter is "necessary". Your motor will probably last longer on some types than on other types. Most likely it will die from overheating from a trashed impellor or water ingestion from rusted manifolds LONG before you can wear it out using cheap oil and filters.

Most people change their oil and filters once a year. Best marine oil and filters you can buy will cost you in the neighborhood of $50. Cheapest crap you can find will cost you around $25.

If you're seriously scrimping trying to save $25 a year on oil changes, you may want to re-consider whether it's the right time for you to own a boat.

 

[Chris1956]

Re: Marine grade oil and filter

BPM, Mercruiser recommends FC-W Motor oil, their own 25W-40 motor oil or straight weight oil. I therefore recommend you use one of those.

They do not recommend any automotive multiweight oil like 10W-30 or 20W-50.

If I were you, I would run the Mercruiser 25W-40 oil. It will cover all the temperatures you encounter. You may use an automotive oil filter to save $4.

 

[Dryon]

Re: Marine grade oil and filter

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.

 

[bpmcl00]

Re: Marine grade oil and filter

well i have decided to use mercruiser 25w-40 blend. and for the oil filter i allready purchassed that one its a napa gold automotive filter