[Vwdiesel] 'H' ...is for honing !

[Val Christian]

I'll check in on this one.  I always thought that one aspect of honing
was to establish a series of micro "ridges", which got leveled when
the engine was broken in.  The friction was less on the ridges than
it would be on a perfectly smooth surface.  (less surface area).
The fact that there is oil in the valleys helps keep the rings
and ridges lubricated.  This helps prevent wear (micro welds, etc.)
Some literature suggest that it's not so much the ultimate cross
hatch marks, as much as it is the porous nature of cast iron which
is responsible for long wear.

Glaze and other debris creates a field with no valleys, as they are
filled, and hence no place for splashed lube to dribble from, and
wear goes up.

Shall I call my friendly team of triboligists?

Val


>
> > "deglaze" so many products would work... perhaps the finer the
> >  better...but as long as  the deposits are removed if any and a matt finish
> > is produced...
>
>   I beg to differ on this opinion (Sorry Mark).  I don't know the logic but
> they
> have gone to some ulra fine honing on some engines recently.  For OUR
> VW diesels however, it don't work.  The purpose of the cross hatching is
> to hold oil, to lubricate the rings.  I was always a bit wary of this being
> the
> whole theory behind the 90 degree cross hatch and all.  Then came my
> Jetta.  So far so good with MY regular, cheap hone.  The machine shop
> hone job wasn't anywhere near as coarse and I was blowing oil in well
> under 15K miles!  The first and only engine I ever assembled with someone
> else's hone job on it.  :P
>      Loren