Sorry the above current specs should read SN not AN. SN is the current API Spec on most current oil viscosity with the exception of some European Manufacturers.

I swear the Merc manual for the 600's called for 20W50 and specifically referenced Kendall GT-1. ;

Although I didn't enter the conversation over viscosity vs protection (valvetrain stability vs oil I guess does not make sense to someone) I will add some proof on the _w-50 oils being proper for many performance sbc/bbc marine engines.
http://www.mercuryracing.com/blog/vital-fluids/
http://outboardparts1.com/merc/13AG41/264.pdf

Mercury 92-8M0053665 FCW® 25W50 Synthetic Blend (1qt)
Mercury 92-8M0078014 FCW® 25W50 Synthetic Blend (4qt)

All Merc Racing stuff now 25W - 50 the new Merc Racing oil is listed. Back years ago the HP 500 carb app use to have listed on its flame arrestor 40 w for motor oil. Also in Mercruiser service manuals straight 40 w was their second listing for all their marine engines no matter what it was except in temps below 50 degrees.

Next Volvo Penta up till 2 years ago recommended straight 30 w syn motor oil.. Now they have changed to a 10w-40.

OMC sterndrives in their day listed 30w motor oil
Next, 7 marine and PCM and Indmar marine LS 557 hp marine engines recommends 5w-30.
Next, all other Indmar marine engines recommend 15w -40 Pennzoil marine except the 557 hp engine.

And here is one, at one time Mercruiser 55 gallon drums at Stillwater plant - black production engines was 15 w -40 Pennzoil marine even though they recommended their own 25w-40,

I don't see it as proof, I see it as preference. Mercury marine is definitely not the absolute go to for oils(obviously they are buying a product and turning around and relabeling making quite a hefty profit). I think you missed out on the conversation I was having with BUP regarding many conventional 50wt oils shearing because of VII. In this case no wonder they spec a thicker oil. With use in many applications it likely shears to a 40wt.

GM has a good understanding of this issue, especially regarding automatic transmissions. Dexron III for example starts out at a viscosity of about 7.5 and many times ends in the 5 range with use. It's a fluid that just didn't resist shear all that well with use. Fast forward to CAFE requirements and DEXRON VI which is a shear resistant fluid. It starts out at about 5.5 and shears very little even after many miles of abuse. Many were confused at how this fluid could be backwards compatible for vehicles specd for Dexron III... Not only is the friction modification adequate(actually many times better in dex VI) but the lower viscosity threshold protects more than adequately in these applications. If the fluid started at 5.5 and sheared, this wouldn't be the case.

So in summation, not all fluids are comparable in service due to formulation and the presence of VII's. Mercury is all about profit and warranty is part of this. Do you really think they would dump dollars into "the best oil" like a shear resistant Ester to run the exact grade for the specified drain interval? I think not. It's a dollars and cents issue, not always what's superior. Case in point, as BUP mentioned previously, Mercury Marines "synthetic" gear oil... What a joke that was... But they are God what they say is gospel.

http://forum.chaparralboats.com/inde...howtopic=23569

All Mercruiser is going to 25W-50 even the cat engines. I could not post the SB from Merc but found it here. I guess this dealer scanned it.

Next Merc HP 525 lists from OEM Service manual # 6 brought to dealers in June of 2003 -
Merc Racing recommends using a 4 cycle marine engine oil (25w-40) or a good grade multi viscosity 20w-50 automotive oil of the correct API classification would be the second choice but less preferable choice.

The listing in chart form as follows. If not using 25w-40 in which think about it who in the world has 25w-40 motor oil expect made to order Mercruiser. ( By CITGO if I recall correctly)

All temps SAE 20w-50 - SH, SJ,SL,CF-4/CG-4
32 degrees and below. SAE 20 W - SH,SJ,SL,CF-4/CG-4
32 degrees thru 50 degrees SAE 30 w - SH,SJ, SL, CF-4/ CG-4
50 degrees and above to whatever - SAE 40w - SH, SJ, SL, CF-4 / CG-4

Everything currently for Mercruiser has changed and if temps are 50 degrees and above they recommend their newer oil 25w-50 syn blend.

The proof is their engines dont blow up!!!! Go try and talk a guy who just dropped 100k on a pair of merc engines into running an oil thats been unproven to work in them, and simply based on your oil research. Good lord.we get it, you dont like 50 grade oils.

Yup gonna use that new stuff next time. :)

Don't mean to change the subject, but. "The proof is their engines dont blow up"!!!! SERIOUSLY Merc engines don't blow up. What a crock.

Did I say it was going to blow to?? Plenty of them do, however that is a separate topic. Mercury marine isn't the engineering powerhouse you think they are.. Jesus you need to read my posts. Were you absent for the explanation of likely shearing that exists in oils with high VII? You always have to get the last word don't you...

Plenty of guys use oil in other forms of Motorsport that tax oils as much if not more than a boat. You act like marine endurance is the epitope of oil abuse. These engines are every bit as expensive, and I can tell you they surely aren't running the OEM high Performace recommendation...

:angry-smiley-038::food-smiley-007:

So why dont we sum it up. Mercury, driven racing, amsoil, mobil, various professional marine engine builders and race teams thousands of oso members, and hundreds of marina service departments have been wrong, by using such an antiquated molasses like oil such as a 50 grade.

Who knew all they had to do was ask borgie and everyone would be running 10w40 redline. Well, if they wanted to do it right that is.

Tonight I am going to compose an email stating my bearing clearances, operation parameters, temperature parameters, rpm range, and fire off some emails to amsoil, redline, mobil 1, valvoline, brad penn, and joe gibbs. I"ll post the replies i get back from them, although it will probably be argued that they dont know everything .

So a recommendation without validation (just running an oil without issue isn't validation) is the last word as far as you are concerned regarding oil viscosity? Thousands? Did you take a poll I'm unaware of? Even so, thousands are running too thick of an oil in many cases. You seem to forget that your engine isn't representative of the "majority" and as you put it "thousands" of boaters and builders that run a 50wt oil. Have any of these companies validated an engine such as yours like they might with a more mild N/A build? Doubt it. In many cases they recommend a one size fits all, in case the end user is neglectful of maintenance etc etc... But that never entered into mercury mind as they are such innovators. The funny thing is that they "use" to be... After their lies about the gear oil being a synthetic and how poor of an oil that turned out to be, they would be the last people to get oil advice from IMO.

Yes, by all means email these companies. Submit the information on your big blown BBC which few people, definitely not the majority of boaters run. And when they say 50wt you can pat yourself on the shoulder. Still doesn't account for the mainstream Performace engines that outnumber the blown engines like what you are running 10 to 1! Interesting information,however hardly a nail in the coffin to what I propose. And just to be clear I never said that you must run redline or any other oil. Just that a 40wt multi viscosity oil is a very good fit in a high output BBC. That being said Ester oils like redline and Motul happen to be shear resistant, unlike mobil 1, and countless other synthetics on the market. Many companies know their oil shears or will be abused with infrequent changes or fuel dilution. What's the safe bet in some of those cases, recommend a 50wt, when often it's not needed. In some cases, sure, however for the maority there is a more scientific approach.

Why do you think UOA's are so crucial for serious racers and even hobbyists? Because without them, you are only guessing and trusting what a oil company is telling you it "should be" doing inside your engine.

For those that don't just take a manufacturers/oil companies word for it, this is the man to consult. If not you are merely guessing and trusting what "should" work.

http://youtu.be/NDE9A9siNeQ

Borgie - do you send an oil filter sample also ?

I have a confession to make.
I once used 4qts. of brad penn 10w-30 and 3qts. of brad penn 20w-50 mixed as a "cocktail" in my stroke small block ford drag racing engine.

:evilb:

Oh, the horror!

A few pages back, someone said there is no magic oil, and to that I reply- balderdash!
I use magic oil. I never have to change it, and it magically disappears. Also, I think it's made at U of M, because it's blue (oil), maize (jug), and never lasts more than part of a season.

For everything else, there's Mobil 1 or Rotella.

The oldest boat I've been doing mainentance on since new is a 1984. Original motor. Tied up to a dock from May to end of October. Get's used few times a week and few times each week-end. For the most part. Has been ski'd and tubed behind for 2 generations of kids now. Long trips, short trips. Been overheated a few times.
Been out of the air a ton of times. Stuffed atleast a dozen times. Drank on. Boinked on. Overloaded. You get the point - a well used 30 yr old boat.

I'm starting to get nervous about the oil I've been using for it's oil changes.

Maybe, I've been using the wrong kind and I've been negeclting it since I have not done MOA's and adjusting to a different type / viscosity.

Wholly crap.

30 yrs old. 2014-1984 = 30yrs.

I hope the owners don't find out that it may not be the best conceivable oil out there and that I've been shortening it's life dramatically because of this.

From your response its apparent you aren't able to think outside the box on this toipic, and that's fine with me. Reiterating "nobody said it absolutely wouldn't work or it would shorten engine life" obviously is going in one ear and out the other..And then you realize lubricants aren't your strong subject so you make elementary jokes. So SAD....

For the most part I've come to expect a lack of understanding on OSO from several members here who think builders are tribologists.. Blenders and major is sciences. OSO is the source of so many oil myths. I recall one major builder who's tied to a major boutique oil company, stated "synthetic motor oil makes roller lifters slide on the lobes". This is just one of many from a significant builder. I realize everyone makes mistakes, however it's funny as synthetic is pretty much all they recommend now...

Nope.

I started to spill some guts about a few yr deal I spent on on some performance issues I saw with many engines and how I found oil was contributing to it.

You kept being a dikhead and attacking me......+ stayin on the lubrication end of it, which I wasn't.

No answer to your experiences and hands on research. Everyone has to prove themselves to you. You don't have to do the same.

So......the last few posts were more entertaining (fun) then what's being put on the table so I'm joining with that.

It's the internet...remember that..as I'm doing now...I have other real life things to worry about / focus on than some overheated religious cult type oil person that always seems to go 'Kujo' on any oil related thread.

I know, you think you are the nice guy and wonder why everyone else is such an azzhole.

So be it. We've had these talks before.

You won't back down.

It will be best for the both of us if we ignore each other. I will try harder with this and hopefully it benefits both of us.

You offered zero evidence or data for the record, so keep the lies coming... You mentioned working in several venues of Motorsport. So?! Where's all the data from that, and how does it pertain at all to this thread?

Regarding you a your few friends thinking I'm an "azz hole" your classy word, not mine, I really could care less pal. I don't come on here trying to impress others. Sometimes my opinion is popular and somtimes it's not. My ego is in check and I stand by my knowledge base and experiences.

Keep creating smoke screens because you have zero educated rebuttal to offer anyone here with regards to the topic at hand, other than absurd mumbling about an old boat, back when you were relevant in Motorsport, and 3rd grade jokes.

The best part about reading these forums are the self proclaimed experts that insist on pointing out the ignorance of the population, but continue to engage in the conversation. It is SUPER entertaining. So, a big thanks to all of you who continue to poke the bear, and a bigger thanks to the bear who can't walk away! (Go Kendall 20w50!!!)

Tell your BRO dallas I say hello! Next time you can address me by name.

The other great part is when folks like yourself make moronic statements! That's why this is truly so much fun. Some here need a cheerleader and you seem to be a perfect candidtate for that....

Reading a thread and contributing nothing, besides tip toeing around insults pointed at me. Big man! That's what people do when they can't hold their own in a discussion.

I ordered an AMSOIL filter....Think that will be Ok?

Damn it....I paid like $13 bucks for that thing and need to know if it's trash or not!!!!

Also bought 15w50 Dominator snake oil....I've heard good things about it from people with 1st hand experience....

$178 to change the oil and gear lube....Ouch....

Damn it....I paid like $13 bucks for that thing and need to know if it's trash or not!!!!

Also bought 15w50 Dominator snake oil....I've heard good things about it from people with 1st hand experience....

$178 to change the oil and gear lube....Ouch....

Id like to say yes. But im about done giving out any advice on oso.

Brad Penn 20w 50 zddp semi synthetic - the "green stuff" :)

^^^^ MILD T - why you post great pics under your name and seem to help out with a lot info.

Oh here I have something to change your mind and to cheer U up.

www.docs.citgo.com/msds_pi/591239.pdf

Im still waiting for the validation that 40 weight oil is just right for the rigors of marine use. Please site your references
Pretty much everyone in this thread, Mobil1, GM, Mercury etc etc says use 50weight. Wheres you rebuttal? Wheres the proof? Wheres the facts that this is not true? Wheres the data that supports your opinion?
Mercury rebrands oil and makes money doing it so they must not know whats best for their motors? Thats your rebuttal?

Thats sums him up perfectly!
Everyone else is an idiot but Borgie.
The way to win an argument is to be as condescending as possible without any facts to support your facts.
As a matter of fact this whole thread is like 100 of the same mind vs. Borgie.

:nhl_fight:

You are kinda like your friends, you don't read the sentences of just ignore the content. You forget why these people "sometimes" recommend 50wt. Not all marine manufactures spec it. You are running your mouth but you have diesel oil in your crank case if you want to spew at the mouth about what's "recommended" in the industry. Not saying it doesn't work, however Mercury, not even amsoil would sign off on that in writing. There are many reasons why.

I've already given explanation of why 40wt will work. Do some more research and you will see my conclusion is correct.

Problem solved, blood pressure reduced.

Posting pics of women that you can never or will NEVER get... Making idiotic posts.. Yeah that sums you up quite well Id say. Riding on the coat tails of your intelligent friends.. Truth hurts bud. You can call it condescending all you want.

Am I in the right thread? Is this the cafe teaser thread? Anyways, Borgie, any thoughts on Joe Gibbs oil?

Lol. It's a great product. I've used their break in oil and their line of mPao synthetics are some of the best money can buy. Pricey, but very robust oils. Unlike quite a few oils discussed here their synthetics have very low NOACK volatility, and a very high viscosity index of around 200. Quite a few traditional synthetics along with a few grades of redline are only in the 160 range. So with this formulation they really designed a well rounded oil.

http://www.drivenracingoil.com/news/...ll-synthetics/

Borgie please do not take this wrong and just pointing out that you discredited Driven from MY post back awhile ago as I use it for my boats and for my higher end customers. I use Driven and some still want VR1 Valvoline or Amsoil in which I carry, sell & use all 3.

And to add to the list, I use Mystik in the black OEM stock apps unless the boat owner wants Merc or Volvo or VR1 or Amsoil per their preference as I carry & sell all plus the OEM oils as well.

When did I say anything negative about them? Please refresh my memory here. I'm not taking it anyway. I find it unusual as they make a very robust product.

I will try to find the post that I replied in. No biggie but you are now asking. I am not up here to take sides with anyone so no jabbing on my end to anyone.

wow,i just came in from the shop and tuned in to oso.this thread,like most all the oil threads turned into a train wreck.jeez,just run the oil that works for you.i sometimes let things bother me that should not,this thread is not one of them!mild thunder,borgie,sb,icdedppl,let it go fellas.mild,don,t let this chit stop you from giving advice,your experiance and knowledge is appreciated by many members,im not going to change my thinking about what oil to use because someone who knows all about oil sais im wrong,i will continue to rely on my and others experiances on what works.in closing i will add that thanks to bup i will be runnling the mystic 15w50 in my fountain.

I'm not taking sides, I'm not a triboligist, and I'm trying to learn.
With that being said, I've been under the impression that if a HDEO/HDDO has an SG/SJ/SM (spark) and
CJ-4/ CF (compression), that meant it met all those listed specs, and when a manufacturer puts on the label that the oil meets those specs, they are kind of "signing off" on using the oil in any of the engines requiring any of those specs. Am I missing something?