Question for the math geniuses. Moly concentration

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Normally a oil will have Moly at around 50-80 parts per million. Some oils like the Idemitsu Mazda Moly oil have 800 + ppm. Different moly of course. LiquiMoly’s MOS2 additive recommends a 2-5% concentration.

So by searching I came up with the answer that 800 ppm = 0.08% which sounds off to me. I am not good at math so can anyone confirm or refute this equation?
 
100% is 1 000 000 ppm (1 million ppm)
10% is 100 000 ppm
1% is 10 000 ppm
0.1% is 1000 ppm
0.01% is 100 ppm

so yes, 800 ppm is indeed 0.08%
smile.gif
 
800/1,000,000 = 0.0008 = 0.08%

Bonus calculation - so a 5% concentration would be 50,000 ppm.
 
So if LiquiMoly suggests a 2-5% dilution of their product into the sump then to get ppm we would have to know the concentration of their product? MSDS didn’t help much
 
Originally Posted By: PimTac
So if LiquiMoly suggests a 2-5% dilution of their product into the sump then to get ppm we would have to know the concentration of their product? MSDS didn’t help much


Part of that problem, is that we don't know the concentration of moly in the liqui-moly product.
 
You would need to know the ppm of Mo in the additive. Maybe you could find a VOA on it. Once the initial Mo conc is known it is:
C1 X V1 = C2 X V2

C1 is the moly conc of the additive
V1 is the volume of additive
C2 is the desired 800 ppm final conc
V2 is the volume of the sump

Solving for V1 we have:
V1 =(C2 X V2)/C1
Or
V1 = (800 X ounces in sump)/Additive PPM
 
Thanks for the formula. I’m horrible in algebra. I’m one of the small subset of boomers that was taught old math then switched to new math and then back to old. Thank goodness for calculators.
 
Try to look at it another way... which is also why people find metric logical...

1 mg is 1/1000 g. 1 kg is 1000g. 1000 x 1000 is 1000000.

1ppm is 1mg of something per 1kg of stuff.

So 1ppm is 1 mg of Mo per kg of oil.

1% therefore is 10000mg of Mo per kg of oil, because there are 100 10000s in 1000000.

Depending upon detector type, it may not care what chemical variant of moly it is.
 
“Depending upon detector type, it may not care what chemical variant of moly it is.”



So what we see in the oil analysis is the measurement of moly as it’s base form, regardless of which type it is ?
(Moly Disulfide versus Moly DTC)
 
Originally Posted By: PimTac
“Depending upon detector type, it may not care what chemical variant of moly it is.”



So what we see in the oil analysis is the measurement of moly as it’s base form, regardless of which type it is ?
(Moly Disulfide versus Moly DTC)



Yes. Most of these 'metals' numbers are measured by Inductive Coupled Plasma (ICP) so relate purely to the specific (or base) 'stuff' . So for example, ICP might measure 1000 ppm (0.1%) of Zinc in an oil but this Zinc will actually exist in the oil as part of 10000 ppm (1.0%) of Zinc Dialkyl Dithio-Phosphate.

Regarding Moly, most of the Moly you see in oils will exist as a fully oil soluble form (Moly DTP, Moly DTC, Moly ester, tri-nuclear Moly, etc) and NOT as Molybdenum Disulphide (which exists in oil as a dispersed but insoluble solid). It bounces about but if you assume 8% Moly metal in an oil soluble Moly, you won't go far wrong.
 
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LM ?

Don't do it. That was the end of my Honda 1.5L in the Fit. 1/3 of a can.

I was duped, you don't have to be.

New car newish engine ... toast.
 
Thanks for the info everyone.

I wasn’t planning to use the stuff Arco, just curious why LM used % instead of ppm . Anyhoo, you seem to have bad luck with with most every brand?
 
Originally Posted By: PimTac
Thanks for the info everyone.

I wasn’t planning to use the stuff Arco, just curious why LM used % instead of ppm .


They say % so you know how much to add to your sump. If you wanted to use a 5% concentration and had a 5 qt sump, then you'd add 5% of 5 qts which is 8 ounces.
 
Originally Posted By: ARCOgraphite
LM ?

Don't do it. That was the end of my Honda 1.5L in the Fit. 1/3 of a can.

I was duped, you don't have to be.

New car newish engine ... toast.


Have you contacted any auto manufacturers yet about possibly becoming part of their durability testing programs?
 
No, I just have an engineering background (mechanical) along with being a NIASE in the late 70's and I know when the car has an issue. 99% of folks just drive their car no matter what, oblivious to the impending failures. Also near redline is not a dusty place on my tachometer.

Two major problems have ben ID over the past decade - Poor flowing/undersized OE service oil filters and poor fuel quality in my neck of the woods.

Poor fuel is a certain engine killer.
 
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