I "think" the problem was when Lycoming switched from alum/bronze pin caps
to aluminum caps. I've been told there is no problem with either the
alum/bronze caps that preceded or followed the aluminum caps, nor is there a
problem with the aluminum "piloted" press fit ends that are pressed into the
pins. Superior also makes pins with press fit plugs, although they problems
with the pins cracking in an earlier version.

Superiors SL points out that you can not mix pins/plugs of different weights
on the same engine.

Can an A&P familiar with the different pins chime in?

Jim


"Robert M. Gary" wrote in message
ups.com...
On Aug 16, 10:33 am, Dave Butler wrote:
Robert M. Gary wrote:
I have an IO-360-A3B6 with 1000 SFNEW in 1998. We pulled a cylinder
and the pin plugs where gone (we guessed this from the oil analysis).
The mechanic says he thinks he remembers some sort of SB put out by
Lycoming that there was a defect in the plugs and that they were made
too soft. Has anyone heard of such an SB???

http://www.lycoming.com/support/publ...structions/pdf...

DB

Well, that's me. Now the cylinders are worn from the busted pin plugs.
That's at least one cylinder that will need to be replaced. I wonder
if Lycoming will offer any assistance ($$$) in addressing this since
the SI seems to acknowledge that the pin plugs were inproper.

-Robert