You'll open a hornets nest with that one.  A proper sized o-ring does NOT need augmentation by any glue,silicon, RTV, etc.  if you feel the need to apply something, I've found KY jel or the equivalent will allow for better seating (less likely to pinch, etc).

Flame proof strap donned. 

Karl Wolz
Sent from my electronic umbilicus

On Dec 1, 2012, at 2:25 PM, Robert Clemmer <n51219@COMCAST.NET> wrote:

> Ok, today I finally got the water pump out.    UPS is scheduled for Monday
> delivery of the new one.  Not too much swearing.  I was surprised to find
> that it wasn't the pump shaft leaking even though it was noisy and a little
> loose, but the O-ring had become hard and lost its seal over the years.    A
> little clean up with the wire brush and I'll be ready to reassemble.  Oil
> pressure gauge will go in the same time while the engine tin is off.
> 
> 
> 
> I think I read here where someone uses a little black silicone on the
> o-ring.  I curious about the pros and cons of using this.
> 
> 
> 
> Bob C