[Shotimes] Re: help.....valve chatter and rod knock...

[Mark Nunnally]

> In most production engines there is enough tolerance in the deck height
that
> the piston won't hit the head until a significant amount of the bearing is
> gone.  I have seen lots of spun bearings and you have to be pretty bad off
> for the bearing to be over half gone.  So at first you probably are
hearing
> the big end of the rod bouncing around on the crankshaft rod journal.

    I was referring to the bearing shells being totally out of the rod cap.
Enough of running around with bearings already going south, before they get
hammered and leave the rod end/crank journal totally.  At this point the
piston is just slapping the head.

The motor in my wife's 91 (bought it like that) did this, and I've seen a
few others.  Guy kept driving it with it knocking, 15 miles from work,
trying to make it home, the piston finally broke apart from hitting the
head, the piston pin stayed on the rod and ripped 2 gashes down the cylinder
walls, and from there the whole grenade went off.  Block even vented piston
ring bits into the intake surge tanks.

mark