Boron/Sodium/Potassium Ratios

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Honestly it depends on the brand. Are you sure B is included? Maybe a borosilicate?

Bottom line is: I have NO idea of the ratios.

Do you suspect a coolant leak? (this is the motor oil forum)
I'm getting positive glycol using ASTM D2982 method for detecting glycol in used lube oil. The reason why I'm asking about the ratios, is that the Spectrometric results are very low (however there are only 300 km on the oil that was tested). A blank oil was also checked for glycol to eliminate any false positives and found to be negative.


What do the results of other mechanical/gas type testing for a leaking cooling system/head gasket tell you?

Via the cooling system: pressure test, exhaust gas tests?

Via the spark plugs: leak down test?
From a UOA point of view,not a virgin sample of coolant), it seems that more boron is being used as an additive and confirmed in the UOA, at least with Amsoil, around 25-30 ppm. Used to be almost nil. Also, if you are burning the coolant via a head gasket leak then the boron may be elevated but difficult to tell. Potassium appears that under 5 ppm is the norm and sodium under 10 seems about right. If you have higher numbers, coolant level in overflow tank is consistently low and you may also see higher lead numbers then a coolant leak is feasible and worth checking out.

[ October 26, 2003, 12:06 PM: Message edited by: Spector ]
A serious coolant leak will generate several hunderd ppm of sodium in the oil. One of my customers had a 7.4L Mercruiser with a coolant leak - his sodium was 725 ppm!

I believe the specific test for coolant only yields a + result if the level of pure EG is > 0.5%, so it's a lot less sensitive.

The Series 2000, 0w-30 has had boron for at least the past five years, but not the regular 5w-30 and 10w-30. They were also using boron in the Series 3000, 5w-30 the last time I tested it several years ago.

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