Oil question

[Rosscoe]

Since I've had nothing but outboards, I dont know if there is anything special about the oil that should be run in a marine V8, so what are you guys using?

[OleRed]

I use Rotella 15/40  it's available just about every where, and in my opinion it's a good aof an oil you can buy for the money.

[Rich_V174SS]

Mercury/Mercruiser has their own concoction of 25w40 for their engines, that's what I use in mine.

[Tonka Jim]

I use the Rotella 15W40 also - Great oil & because I'm in truck equipment sales I get it cheap.

 

[Jason]

This thread is going to get really long and HEATED. Everyone has different opinions. I use the Mercruiser 25-40 too but it's expensive!

[Rosscoe]

Now now boys. It doesnt need to get heated.
Thats why we're here at least in part. To share ideas and knowledge.
Yeah I imagine the merc stuff is expensive but the guy that rebuilt my merc swore by it and insisted I use it in there and I do.
I've seen Rotella at Fleet farm if I'm not mistaken. Think you can buy it in couple of gallon containers.
thanks guys.

[wexrocks]

I certainly don't have the answer to this one, but, after talking to a few engine builders, they all said the same thing... Most oils in the last few years changed some things to save money, and one of these was dropping the added zinc, which without it will aparently wipe out flat tappet cams. Some say they add diesel oil to help with this. And aparently some oils still have it. I have no idea which ones, and I can't say this is absolutely true, but like I said, they all offered the same info, so that may be a point to research. I will likely go full roller with my 454, which I have been told will be perfectly safe with synthetics. But of course, full roller isn't cheap!

Anyway, just thought I would add this, maybe someone knows more about this. Apparently this difference is more important the higher horsepower you go, but may be important in making stock engines last as well. I know I'll be looking into this topic alot more before I fire my engine. They all did recommend conventional oil for break in, then switching to a high zinc or synthetic (with newer or converted roller motors). Anyone have any insight on this?

[Tom]

In my 69 Chev truck my engine builder said to use Rotella because it has zinc.   I have always used Vavoline Racing 20w-50 in my CV23 and Supra.

[Rosscoe]

Interesting. Zinc mentioned more then once. I'm going to check out the labels and see if it actually identifies it as containing zinc.

[Eric_Michael]

Interesting. Zinc mentioned more then once. I'm going to check out the labels and see if it actually identifies it as containing zinc.

I have always used General Motor's Engine Oil Supplement (AKA: EOS, GM Part #8862586) in my collector vehicles.  It has all that wonderful zinc that modern oils leave out.

I toyed around with Google and found where someone had a sample of EOS submitted for analysis.  Here is a scan of the report they received:

http://i179.photobucket.com/albums/w297/haywardone/Scan002February142008-1.jpg

Spendy stuff though.  About $20 for a pint.  Cheap insurance though if it saves a rebuild.

-Eric

[GT150 JEFF]

I use Rotella in my engine after installing new cam and lifters because of the zinc in it.

Very true that with out zinc it will wipe out a flat tappet cam and lifter set up.

I believe after break in you can use what ever you want but I will stay with Rotella

[Rosscoe]

Interesting. Zinc mentioned more then once. I'm going to check out the labels and see if it actually identifies it as containing zinc.

I have always used General Motor's Engine Oil Supplement (AKA: EOS, GM Part #8862586) in my collector vehicles.  It has all that wonderful zinc that modern oils leave out.

I toyed around with Google and found where someone had a sample of EOS submitted for analysis.  Here is a scan of the report they received:

http://i179.photobucket.com/albums/w297/haywardone/Scan002February142008-1.jpg

Spendy stuff though.  About $20 for a pint.  Cheap insurance though if it saves a rebuild.

-Eric

Eric how much of that do you add? A pint at oil changes?
That leads to other questions about oil changes. Go by hours?

[Eric_Michael]

Eric how much of that do you add? A pint at oil changes?
That leads to other questions about oil changes. Go by hours?

I put the full pint in when I change the oil.  I short the oil a bit so as to not overfill the crankcase.

I do annual oil changes on the car.  It does not get enough annual miles on it to even come close to being at the end of the oil's service life.  But considering it sits 99% of the time, I figure there will be moisture & other contaminants which will have been at work breaking down the oil's efficiency.

[Jerry]

The guy that built all my drag race motors used EOS for assembly lube. He swore by the stuff.

[TomLund]

well i have used lots of different oils because i changed mine so much with water in it.lol  I  will use mercruiser when i know i don't have to change my oil every week