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Of battery terminals & grease

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Fester Bestertester

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Feb 24, 2015, 1:37:03 PM2/24/15
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There are some members of electronic forums that suggest coating automotive
battery posts with grease ("any king--axle, lithium, copper") before
attaching cable-end clamps to the posts and swear that it doesn't affect the
connection adversely.

Are they nuts? Grease between terminal elements?

What grease--if any--is best, inside or outside the terminal connection?

Thanks.

Scott Dorsey

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Feb 24, 2015, 1:55:04 PM2/24/15
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Fester Bestertester <f...@fbt.net> wrote:
>There are some members of electronic forums that suggest coating automotive
>battery posts with grease ("any king--axle, lithium, copper") before
>attaching cable-end clamps to the posts and swear that it doesn't affect the
>connection adversely.
>
>Are they nuts? Grease between terminal elements?

It's fine, because the posts are soft lead, and so is the terminal lug, and
so they deform to fit one another squeezing all the grease out except in places
of poor contact anyway.

>What grease--if any--is best, inside or outside the terminal connection?

Dielectric grease is good, but you can also purchase a strongly reducing
"battery protectant" material in a spray can which is grease-based and works
well.
--scott
--
"C'est un Nagra. C'est suisse, et tres, tres precis."

John-Del

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Feb 24, 2015, 2:19:15 PM2/24/15
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On Tuesday, February 24, 2015 at 1:37:03 PM UTC-5, Fester Bestertester wrote:
> There are some members of electronic forums that suggest coating automotive
> battery posts with grease ("any king--axle, lithium, copper") before
> attaching cable-end clamps to the posts and swear that it doesn't affect the
> connection adversely.

I've always understood it to be that any grease you apply will not interfere with the contact of the metals which occur at the molecular level. Any grease not squeezed out will occupy the space that air and moisture would occupy otherwise.

I've always put a thin coating of dielectric grease between the post and terminal, and have never had a bad connection at a battery since. If there is any interference by the grease, it must be offset by the terminals remaining free from oxidation.

Dave Platt

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Feb 24, 2015, 2:35:37 PM2/24/15
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In article <0001HW.D11204CB...@news.eternal-september.org>,
Fester Bestertester <f...@fbt.net> wrote:

>There are some members of electronic forums that suggest coating automotive
>battery posts with grease ("any king--axle, lithium, copper") before
>attaching cable-end clamps to the posts and swear that it doesn't affect the
>connection adversely.
>
>Are they nuts? Grease between terminal elements?

Not nuts... clamps :-)

The trick here is the fact that the clamps are tightened down
well when you install the battery cables. The tightening pressure is
sufficient to force the surface of the metal clamp into direct contact
with the (soft) lead battery post, squeezing all of the grease
out of this area.

You end up with just about the same amount of direct metal-to-metal
contact between post and cable-clamp that you would if you hadn't
used grease. The grease which remains, fills what would otherwise be
air voids between the post and the clamp. The grease will block
oxygen and moisture (including leaked battery electrolyte) from
penetrating the connection and thus will help preserve the quality of
the metal-to-metal connection.

>What grease--if any--is best, inside or outside the terminal connection?

http://www.w8ji.com/dielectric_grease_vs_conductive_grease.htm

"In single low-voltage terminals or connections, such as metal-to-metal
joints, grounds, or battery posts, almost any pure grease of light
viscosity will be acceptable. Caution should be used with greases
containing metallic powders to be sure any metal is compatible with
the embedded grease metal. Connection enhancement from embedded metal
powder is very minor, if it exists at all, and there is increased risk
of bad connections if the metal powder has any interaction with the
base metals."




John Robertson

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Feb 24, 2015, 2:59:05 PM2/24/15
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Grease can improve electrical connectivity if designed for that purpose
- check out Dow Corning #4 dialectic grease - we use it on many power
connectors and it not only reduces contact friction, and protects
against oxidation, but the connector actually is often cooler than one
without the grease added!

John :-#)#

--
(Please post followups or tech inquiries to the newsgroup)
John's Jukes Ltd. 2343 Main St., Vancouver, BC, Canada V5T 3C9
(604)872-5757 or Fax 872-2010 (Pinballs, Jukes, Video Games)
www.flippers.com
"Old pinballers never die, they just flip out."

mog...@hotmail.com

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Feb 25, 2015, 8:39:11 AM2/25/15
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On Tuesday, February 24, 2015 at 1:55:04 PM UTC-5, Scott Dorsey wrote:
>
> --
> "C'est un Nagra. C'est suisse, et tres, tres precis."

Et vous aussi vous faites Charlie?

micky

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Feb 25, 2015, 1:35:44 PM2/25/15
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On Tue, 24 Feb 2015 11:58:37 -0800, John Robertson <sp...@flippers.com>
wrote:

>On 02/24/2015 10:36 AM, Fester Bestertester wrote:
>> There are some members of electronic forums that suggest coating automotive
>> battery posts with grease ("any king--axle, lithium, copper") before
>> attaching cable-end clamps to the posts and swear that it doesn't affect the
>> connection adversely.
>>
>> Are they nuts? Grease between terminal elements?
>>
>> What grease--if any--is best, inside or outside the terminal connection?
>>
>> Thanks.
>>
>
>Grease can improve electrical connectivity if designed for that purpose
>- check out Dow Corning #4 dialectic grease - we use it on many power
>connectors and it not only reduces contact friction, and protects
>against oxidation, but the connector actually is often cooler than one
>without the grease added!
>
>John :-#)#

Yes.

I wouldn't use non-conductive grease on a battery post because the
connection will not always be as tight as it should be.

They sell small envelopes of dielectric grease at the parts counter of
consumer autoparts stores, like Pep Boys, Autozone. The size of
envelopes of ketchup and on a rack next to others with
brake-pad-anti-squeak. spark-plug-anti-sieze, and a couple other things.
It costs between 1 and 2 dollars. Enough for two cars, at least.

They have the envelopes at real autoparts stores too, but not right
there on the counter.

Do some cars still come with spring loaded battery-cable ends.? They
can't be tightened any more than the spring inside makes them tight, and
they eventually get loose, regardless of grease. When they're not
tight enough, they should be cut off and replaced with an add on
cable-end, or if there's not enough slack, a whole new cable. Even on
those with bolts for tightening, I've seen the bolt or nut or the lead
that holds the bolt in place get stripped and require replacement.

If when the car is runnning or you're cranking the engine, the battery
post and the clamp surrounding it are hot to the touch, the connection
there is bad. A good connection will not be discernably hotter than
"room temperature." Backwards from the way it might seem.

With a battery cable at the battery post, after it cools enough that you
won't burn your hand, or with a leather work glove, you can very often
have success by grabbing the cable and rotating it around the post 10 or
30 degrees, and then pushing it back where it was (and pushing down at
the same time, so it might be on a little tighter) It's likely to be
loose enough to do this, because if it weren't loose, you probably
woudn't have the problem in the first place. Also buy a battery
post/terminal brush. Two brushes in one piece, for 4 dollars in
plastic, 6 in metal. You'll need to use this whether you use grease or
not, before you put on the grease. . One brush should last you for the
rest of your life.

I've never used such grease on battery posts, and I've never had a
problem there. But some people might. With a '65 Pontiac, I had
major connection problems between the positive battery cable and
everything else at the starter motor. If I left the headlights on for
two hours or more when the car wasn't running, the starter motor would
barely turn, even if the battery was jumped. I don't think such grease
was easily available in 1969. It certainly wasn't on display at the
parts counter. Maybe it would have solved the problem.

After the new car dealer where my brother bought it replaced the
starter, alternator, and regulator twice each, they said, and then
woudlnt' try fix it anymore (even though they had never fixed it)
because they said the two-year warranty had expired, my brother went to
Viet Nam and gave me the car. and when I took it to Sears for one more
battery, they found the problem for free in less than 5 minutes. What
the dealer couldn't find in 2 years. The Sears man took apart the
connection and scraped or cleaned the parts. When it happened again
(after leaving the headlights on) at first I took it apart too and
scraped the parts with a knife, but eventually I learned to reach under
the car, grab the battery cable and pull it towards me once and push it
back once. I could do this in nice clothes without even getting dirty,
except my hand a little bit. Maybe you can't do this with a compact or
small car. Eventually I came across a buzzer that buzzed when the
lights were left on and that solved the problem .

When I got to my brother's city three years later, the dealer was out of
business. Maybe because they didn't know how to fix a car.

m II

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Feb 26, 2015, 3:52:05 PM2/26/15
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On 15-02-24 11:36 AM, Fester Bestertester wrote:

> Are they nuts? Grease between terminal elements?
>
> What grease--if any--is best, inside or outside the terminal connection?

The only purpose of the grease is to keep the elements out of the
connection. Clean terminals and clamps thoroughly. Use baking soda mixed
in water if there is any encrustation and keep the resulting froth out
of the battery cells. Dry with a paper towel then smear everything with
Vaseline and reassemble. Tighten. wipe any excess forced out Vaseline
off. It's worked for thousands of users for the last few eons. A few
posters seem to think 'dielectric grease' means conducting...it doesn't.

In the electrical field there is an anti-oxidant grease called No-Alox
or Penetrox. It's a greasy paste with what may be metallic particles in
it. The only purpose of that is the same as above..it keeps
moisture/oxygen out of the joint to prevent aluminium or copper oxides
from forming. Those are non-conductors, as is the anti-oxidant paste itself.



mike



--
It is hard enough to remember my opinions, without also remembering my
reasons for them!

Friedrich Nietzsche

gregz

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Feb 28, 2015, 3:13:17 AM2/28/15
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I used to put some kind of lube on. I guess I still do. I seem to recall
old radio books saying to use Vaseline. I always rock the clamp into the
posts. Seems like lube would help it get down deeper. I'm seeing new
recommendations of spraying the completed connection with fast drying
varnish or lacquer, instead of greasing the whole thing, assuming it's
clean.

Greg

dave

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Feb 28, 2015, 9:56:14 AM2/28/15
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I don't go anywhere near my batteries with baking soda. I don't let
mountains of oxide build up, either. Put grease on after assembling
connections. It is to keep air out. Flux brush and petroleum jelly.
Whatever.
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