Ferrari Mailing List: Re: Cleaning femal ends of relays procedures and spark plugs

[Todd Walke (racertod]

Michael wrote:

> O.k. I
> followed someone's advice and bought the aerosol can to clean the female
> ends of the relays. The clerk told me to unplug the negative on the
> battery and shoot the spray inside the slots (female ends) of the relays.
> Wait 15-20 minutes and put eveything back together. Anything else I need
> to know ?

        

I'm a fan
of using dialectic grease on connectors to help minimize corrosion. 
Here's a quick primer on why, for those less technically 
minded.

        

Although
metal connectors may appear to be very smooth to your eye, on a
microscopic level they look like mountain ranges with high and low
spots.  When you slide a terminal into its receptacle, only the
"peaks" of the mountains contact and conduct electricity. 
The "valleys" contain just air.  Air contains moisture and
that moisture can lead, over time, to corrosion getting started in the
connection.

        

Sometimes
just removing and reinstalling a connection will break the corrosion,
expose clean metal and allow for electricity to flow once again. 
The contact cleaning spray you used is designed to clean off any
corrosion or dirt and get the metal nice and clean.

        

If you
apply some grease to the terminal first, it will fill in the
"valleys" and prevent moisture from getting in there and
causing corrosion.

        

Can you
use just any old grease?  No.  The grease must be
non-conductive.  If the grease conducts electricity, some
electricity may leak through the grease to an adjacent terminal (in a
multi-terminal connector) or to a ground.  That isn't 
good.

        

So we use
a grease with a high "dielectric strength".  Dielectric
strength is a measure of how good of an electrical insulator a material
is.

        

It's
commonly called "tuneup grease" as well as "dielectric
grease".  Here is a link to the Permatex product that you'll
likely find at any parts store:
<http://www.permatex.com/products-2/product-categories/specialized-maintenance-repair/electrical-system-maintenance/permatex-dielectric-tune-up-grease-detail>

        

I use just
a dab on each terminal before sliding them together.  I recommend it
on engine compartment or undercar connectors that may be exposed to
water.  Doesn't hurt on connections inside the car, especially on
cars that may sit for longer periods of time.

        

Newer
cars, like my '01 Golf, have sealed connectors with seals that keep water
away from the wire terminals inside.  Older cars don't use many
sealed connectors and so dielectric grease can be an excellent way to
limit electrical issues long term.

Todd
Seattle,WA
'86 GTI, Red of course. (exciting racey car) 276,000 miles
'01 Golf TDI, silver.   (new work car)       480,000 miles
'87 Golf, Polar Silver. (retired work car)   654,000 miles <- Gone to a new home :(
http://www.pureluckdesign.com <-Ferrari & VW stuff