Help: Oil Samples from Mag 496 w/56hrs

johnfell

Recruit
Joined
May 21, 2009
Messages
2
I need some help understanding the results:

How could seawater and aluminum be getting into the oil?

Here are the details:
Boat: 2005 bowrider w/ 496Mag Bravo III
Hrs: 56 hrs on engine and approx. 10hrs on this oil sample
Compression tests: 190,185,190,185,185,185,190,190 (1,3,5,7,2,4,6,8)

Oil results:
Aluminum 33
Chromium 0
Copper 13
Iron 30
Lead 3
Tin 3
Silicon 22
Potassium 20
Sodium 133
Water <0.1
Oxidation 8.6
Visco@100 13.7
Glycol ND
Fuel <2.0
Nitration 3.6
SAE 43

Could there be one solution to both the Aluminum and Sodium?

Thanks,
John
 

Mkos1980

Chief Petty Officer
Joined
Oct 25, 2007
Messages
640
Re: Help: Oil Samples from Mag 496 w/56hrs

I'd also post this question on bobistheoilguy.com Those guys are nuts with their oil and they'll be able to answer that question in 1 second lol.
 

HT32BSX115

Supreme Mariner
Joined
Dec 8, 2005
Messages
10,083
Re: Help: Oil Samples from Mag 496 w/56hrs

Hi John,

well, one source of aluminum is the 8 round pieces of aluminum flying back and forth in 8 iron holes.......(pistons in cylinders)

With only 56 hrs on the engine it's barely broken in....so aluminum might be expected.....along with the iron they're sliding against...

If this is your first and only test I wouldn't be too concerned. If it was the 5th test and aluminum was increasing you might want to determine why.


Sodium might come from sea water. There is a path for water to get into the engine via the exhaust system. As hard as we try to prevent it you might have had a little reversion from the exhaust system.....maybe not enough to cause a hydrolock but enough to be detected in the oil.

Again, if this were the 5th test and you had it EVERY time you might want to be concerned.

After only one test, it could also be a sampling error or a testing error.

One test doesn't really tell you much...


Cheers,


Rick
 

JustJason

Vice Admiral
Joined
Aug 27, 2007
Messages
5,321
Re: Help: Oil Samples from Mag 496 w/56hrs

may i ask why your actually sending out an oil sample? It sounds a little over the top. Is there an issue your having???

Unless you have some kind of baseline from Merc (which i've never seen) sample results are useless unless you have something to compare it to. I can only imagine because of about a million different reasons that you can't compare an oil sample out of a car to a sample out of a boat.
 

bruceb58

Supreme Mariner
Joined
Mar 5, 2006
Messages
30,603
Re: Help: Oil Samples from Mag 496 w/56hrs

To me, doing oil sampling on a boat engine is a complete waste of time and money. Your engine isn't going to wear out from a lot of use. You have 56 hours on a boat that is 4 years old. That's 14 hours a year! A boat engine will last over 1000 hours easy. It's also not likely you are going to be wearing out the oil. Just change it at the end of every season and you will be fine.
 

Howard Sterndrive

Rear Admiral
Joined
Nov 5, 2008
Messages
4,603
Re: Help: Oil Samples from Mag 496 w/56hrs

Aluminum 33
Copper 13
Iron 30
Lead 3
Tin 3
Silicon 22
Potassium 20
Sodium 133

That's all normal for used oil. Nothing to be concerned about there.
conventional antifreeze contains sodium. a funnel that's used for both could show sodium in the oil. Looks like they did a blot test ("Glycol ND") that didn't show antifreeze.
However,
Sodium at that concentration is harmless in oil and is only considered high if it is 20ppm higher than a sample of the new oil.
Without a sample report of your new oil, there's no way to interpret the 133.
The engine isn't done break in yet so oil sampling a bit premature.
 

johnfell

Recruit
Joined
May 21, 2009
Messages
2
Re: Help: Oil Samples from Mag 496 w/56hrs

The oil samples were done w/survey to check out the boat before purchase. During the survey the engine went into guardian mode after 1min at WOT. According to the sellers mechanic the problem is a water restriction at one of the manifolds. The seller is having both manifolds replaced along with the waterpump impeller. The report from the lab on the oil samples defined the Aluminum content as excessive and the sodium level as abnormal. The seller seem agreeable to fixing the problem. I just want make sure i'm not missing something major.

Appreciate all the input.
John
 

bruceb58

Supreme Mariner
Joined
Mar 5, 2006
Messages
30,603
Re: Help: Oil Samples from Mag 496 w/56hrs

OK...that is understandable on why the oil sample was done.
 

JustJason

Vice Admiral
Joined
Aug 27, 2007
Messages
5,321
Re: Help: Oil Samples from Mag 496 w/56hrs

The report from the lab on the oil samples defined the Aluminum content as excessive and the sodium level as abnormal

The only question I have is this.... compared to what? What is their baseline?
 
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