Metal Napthenates

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Staff member
Jun 5, 2002
Iowegia - USA
Regarding the Topic of Oil Analysis and Pb or lead values: (Whence cometh the lead, bearings or Additives?)

I did some further research and "lead napthenate" was used as late as 1999 as an FM/EP additive, albeit in small concentrations. It reacts very much like MoTDB (Moly) in that it appears in concentration at first and then "uptakes" to the metal to bond to it.

This additive could be showing up as the higher lead values we see. IF this is the case, then it could POSSIBILY mask the onset of bearing wear.

It appears that zinc and bismuth napthenate may be slowly replacing this additive as an FM/EP additive. The part that still buggs me is, if it is part of the additive package, it wouldn't show up because no labs are testing for bismuth, as far as I can determine!!!

The labs show the normal wear metals and some trace elements, but the more exotic metals are not being shown for the $15-25 tests.

The Quest continues!


Do the labs with which you're associated have the capability to detect some of the more exotic elements such as bismuth??
Molekule, We can test for just about any substance including bismuth, I can't get it done under the $25 trend analysis though. If you need it email me and I'll get a quote.

The lead napthenates you are refering to have been used in some fuel additives but none in motor oils I can recall right now.
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