[T3] ? Mystery of the Clacking Valves ?

[Jim Adney]

On 12 May 2011 at 21:16, sploogemeister wrote:

> --- On Fri, 5/13/11, Jim Adney <jadney at vwtype3.org> wrote:

> > That's what I would expect, but I've never seen a failure
> > like this.
> 
> I have, it's actually becoming more common with the removal of ZDDP.
> A lot of older engines, not just our air coolers, need it. Schneider
> Cams and others have done tons of research into this, and the removal
> of ZDDP has been determined to be the major contributing factor to cams
> & lifters "going flat".

The big question for me then, is what do modern engines do to their cams to 
make them survive? Their must be a solution that we should be able to take 
advantage of, even if it means new cam and lifter technology.

> > I keep thinking there must be something else wrong that
> > we've not 
> > thought of, like the head studs pulling out, but more
> > likely 
> > something trivial that has just escaped us all.

> If the studs were pulling, wouldn't there be a major compression leak,
> especially since it's happening to all of his cylinders? I'm sure the
> noise from the leak would be considerably noticeable.

Right, I don't think it's the head studs, but then what is it?

-- 
Jim Adney
jadney at vwtype3.org
Madison, WI USA