Lead in oil

[Louis-Alain Richard]

Just to be sure everyone knows about lead in oil.

Engine bearings for crankshaft, rods and camshafts are made of a special
porous metal called "Babbitt" that contains lead. 
http://en.wikipedia.org/wiki/Babbitt_(metal)

So, this explains why some lead could be found in oil analysis. In normal
usage, concentrations should be minimal (a few PPM) as bearings should last
hundreds of thousands miles before needing replacement. From what I've seen,
I've rebuilt a few engines, the bearings shells are steel-backed with a thin
layer of copper over which there is the Babbitt material. So maybe copper in
oil would be a more significant telltale for engine bearing wear ?

Secundo, in Europe, in fair weather countries, oil changes intervals could
reach 30 000km (20 000 miles) and not just for diesel engines. Even the
lowly 2.0L ABA engine from the MK3 Golf as such an interval. So you're not
extending yours too much if you live where water don't freeze during winter.
Cold starts are very hard on oil, more than anything else.

Louis-Alain


> -----Message d'origine-----
> la part de Michael McLaughlin
> 
> Thanks for the response. I believe the engine block is indeed iron.
> I've been running Mobil 1 5W-40 for the most part, and will look at
> chaging the weight. The first oil change I went 10K on synthetic, then
> bumped it up to 12.5K at the suggestion of Blackstone.
> 
> The engine uses a bit of oil -- takes a quart or so every 1,500 miles
> or so -- so I figure I'm adding so much oil that going with long oil-
> change intervals isn't so bad.  :-)
> 
> -Mike
> 
> On Sep 5, 2010, at 1:38 PM, NIck Miller wrote:
> 
> > Nothing that I can think of... The block in your car is aluminum or
> > Iron, do you know?  I don't but I assume its iron.  Not sure.
> >
> > If it is in regard to bearing wear, do you run the proper weight oil
> > for the engine?  perhaps go to a 20w40 and see if the number
> > changes, this will offer better protection for the engine/bearings
> > because of its increased viscosity, but will hamper the engine ever
> > so slightly for the same reason, and it would technically lower the
> > power output by a few, at most 2-3hp, in any test I've ever seen.
> > So little so that its negligible and within the error range in some
> > tests on some dynos...
> >
> > Anyway, I assume you're intervals for oil changes are around 8-10k
> > if you are using analysis, not much I can think of other than do you
> > use Cheap 87 octane gas, and maybe bump up the viscosity of the oil
> > you use if you think the bearings are wearing too rapidly.