Sodium in Oil Analysis

[mooneyflyer]

Got my Blackstone report and it showed SODIUM.  It went from 0-1 to 24.  What is a source for Sodium in an IO550?

thanks

 

[ArtVandelay]

Got my Blackstone report and it showed SODIUM.  It went from 0-1 to 24.  What is a source for Sodium in an IO550?
thanks
 

Valve stems are filled with sodium on Lycoming engines, don’t know for Continentals.

[carusoam]

Do we have an oil report expert onboard MS?

See if Paul at Savvy could give any input on how to tell if an exhaust valve has lost its Sodium..?

Sodium filled valve stems are designed to improve heat transefer from the valve out to the oil...

PP thoughts only, not a mechanic or oil expert...

Best regards,

-a-

[jaylw314]

IIRC, Lycomings have sodium filled valves but Continentals have solid valves.

OTOH, a source of sodium could be sea salt, if you're near the ocean.  I would imagine your air filter would not filter out salt particles.

[CaptRJM]

If you lost the sodium out of a valve you'd have a lot more problems than high sodium level in your oil.

[mooneyflyer]

Continental does not fill their exhaust valves with Sodium. 

Any other ideas?

[mooniac15u]

Sample contamination is always a possibility.  How did you sample?  What kind of container was used?  Was it in any other container or tubing between the engine and the sample vial?

Do you use any oil additives?

[jaylw314]

Eating French fries and potato chips while taking the sample?

[OR75]

ask for no salt when you get  margaritas

[OR75]

sodium can come can come from grease compound  

maybe your oil sample was contaminated with grease ?

[PTK]

On 10/29/2017 at 4:37 PM, mooneyflyer said:

Got my Blackstone report and it showed SODIUM.  It went from 0-1 to 24..

Na!!  can't be, no way!

[DXB]

Blackstone provides pretty detailed support on request, included in the premium price of their analysis, and their perspective based on having looked at a gazillion tests is relevant.  Definitely email them if you haven't already - I'm curious to see how they respond.

[MARZ]

Have you recently started to use camguard? Changed oils?  maybe put some non aviation oil in?    typically additives or contamination add sodium

[astravierso]

mooneyflyer,

As everyone has said generally sodium is found as an additive (corrosion inhibitor) or a contaminant. The contamination can come from multiple sources, sampling technique, sampling supplies, grease, dirt ingestion. Again this has been stated previously. 

I am not trying to sound like a jerk. If you would like a little more help in narrowing down the issue you may want to give a bit more info like oil type, hours on the oil, area the plane is based, other maintenance performed between samples, who pulled the sample and the technique, were there any other elements which were elevated besides the sodium on this sample or any other elements which have been trending higher over previous samples. The obvious reason for all this information is to understand the environment the engine is operating in to narrow down the potential causes

Also the test which gave you the result has limitations which need to be accounted for. I believe Blackstone use an ICP unit to burn the oil (most high volume labs do). What this means is that the 24 ppm you are seeing on the report is 24 ppm at a particle size no greater than 3 to 5 micron max. any particle above that size is not seen by the test machine's optics

Also as stated earlier there are other test which can be ran to help narrow down the issue. A PQ will tell you about the level of contamination in the oil (great than 5 micron), Laser Net Fines or Analytical Ferrography will tell about the type of wear particles in the oil (cutting, sliding, spallling, etc.). The choices are only limited by your wallet. You can also have them re-run the spectral analysis on that sample. While I am not sure of Blackstone's procedures, most labs will keep your sample for 15 to 30 days after they send you the result "just in case" for this reason. 

With all this said and given the information available, I would go with contamination of the sample IF there are no other elevate element on this sample or tends on previous samples. IF you have elevated silicon and boron (and possibly iron and other metals)  I would look at you air intake system as all three elements USUALLY occur together in dirt. IF you have elevated iron and chromium only you want to look at your valves if there are sodium filled.

Just my thoughts, not an A&P or an expert of any kind. Hope this make sense.

Cheers,

Alan