Dielectric grease on connections

zing99

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Mar 22, 2009
Messages
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I'm in the process of replacing my battery cables and switch. Will putting dielectric grease on the terminals at the switch post cause a problem? What about at the starter solenoid? I had in the past been applying a light coating of grease to the lugs and then using marine grease to cover the whole thing after tightening.
After reading some other posts it looks like maybe I should skip the dielectric on the lugs.
 

Bondo

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Re: Dielectric grease on connections

Ayuh,.... After everything is tightened up, I slather plain ole grease on the fittings to stop corrosion...
 

zing99

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Mar 22, 2009
Messages
16
Re: Dielectric grease on connections

Thanks guys, I cleaned everything up with a scotchbrite pad and gave it a coat of omc tripleguard.

Just put in new battery cables and main switch, what a difference.
 

jhebert

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Jul 24, 2005
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Re: Dielectric grease on connections

Will putting dielectric grease on the terminals at the switch post cause a problem?

Dielectric grease is an insulator. Do not use it on the contacts or connections themselves. For low-voltage circuits an expensive dielectric grease is not needed. Those greases are for high-voltage applications. The grease is applied to help seal the connector. It is not applied directly to electrical contacts.
 

Woodnaut

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Jul 4, 2007
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Re: Dielectric grease on connections

About 200 Electronic Technicians in the company I work for conduct instrumentation maintenance on monitoring and control systems around the world both on land and offshore. We use dielectric grease on nearly all signal and power connections - expecially on the offshore applications. Applying a light coat of grease to the contacting surfaces will inhibit corrosion and exclude moisture. The grease should be applied to the clean metal before the connections are made - it will not inhibit the flow of current if the connection is made properly. I have been using dielectric grease on everything from 4-20 mA circuits to battery terminals for many years with no problems whatsoever. However, I am referring to permanent (or semi-permanent) electrical connections here - not relay contacts or switch contacts. Do not overdo it - a light coat is all that is needed. I realize that the grease in non-conductive and that this might be counterintuitive, but the information I am presenting here is accurate. Corrosion is what kills a properly designed electrical connection and the dielectric grease can prevent this. You can also use a small amount of dielectric grease inside of crimped terminals (prior to crimping) to prevent corrosion in those applications. We also use a liquid spray product named Corrosion-X which does an excellent job.
 

TerryMSU

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Jul 31, 2007
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743
Re: Dielectric grease on connections

Dielectric grease is an insulator. Do not use it on the contacts or connections themselves. For low-voltage circuits an expensive dielectric grease is not needed. Those greases are for high-voltage applications. The grease is applied to help seal the connector. It is not applied directly to electrical contacts.

I disagree. I personally use it on most all of my electrical connections with no known issues. I especially use it on light bulb bases. Permatex is one manufacturer of dielectric grease. This is what they say on their web site.

Protects electrical connections and wiring from salt, dirt and corrosion. Extends the life of bulb sockets. Prevents voltage leakage around any electrical connection. Also prevents spark plugs from fusing to boots. Required for modern high energy ignition systems.

Suggested Applications: Marine and automotive electrical connections, spark plug boots, trailer hitches, battery terminals.

They also say, for another type of dielectric grease, the following...

Permatex? Bulb/Lamp & Electrical Connector Dielectric Grease

Increases performance and extends service life of bulbs and lamps by preventing voltage leakage and protecting electrical connections from moisture, dirt and corrosion. Great lubricating properties ease the disassembly process. Protects rubber, plastic, ceramic and metal surfaces.

Suggested Applications: Headlamps, lighting bulbs for: instrument panel, glove compartment, inside door trim, interior courtesy lamps, parking and turn signals, brake lights, license plate lights, trunk and hood lamps; also for fuses, battery terminals, ignition components and other electrical connections.


Admitedly, some of this is manufacturing hype, but some of it is appropriate.

So... Has anyone ever seen any issues that they can actually blame on the use/misuse of dielectric grease?

TerryMSU
 

Grandad

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Jun 7, 2011
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1,504
Re: Dielectric grease on connections

Agree with Woodnaut. The term dielectric refers to the grease's non-conductive properties, such that it will not conduct electricity from terminal to terminal where grease might bridge between them. Applying dielectric grease to a conductor or terminal before connection is made will not provide any significant insulation value. - Grandad
 

TerryMSU

Senior Chief Petty Officer
Joined
Jul 31, 2007
Messages
743
Re: Dielectric grease on connections

Agree with Woodnaut. The term dielectric refers to the grease's non-conductive properties, such that it will not conduct electricity from terminal to terminal where grease might bridge between them. Applying dielectric grease to a conductor or terminal before connection is made will not provide any significant insulation value. - Grandad

When I use it my intent is...
protecting electrical connections from moisture, dirt and corrosion. Great lubricating properties ease the disassembly process.
TerryMSU
 

floater212

Petty Officer 2nd Class
Joined
Nov 27, 2013
Messages
145
i am redoing my stereo system, new head unit and amp, with all the RCA style connectors it has i would like to use the dielectric grease on them for corrosion protection, granted the system is under the dash, i have seen condensation under there a few times ( not a lot of air flow under there), so because of that it's better to be safe than sorry. IMHO.
 

roscoe

Supreme Mariner
Joined
Oct 30, 2002
Messages
21,657
Coat battery and crimp connections with OX-Gard.
It is a conductive grease. Prevents corrosion.
Often used by electricians when connecting dis-similar metals.
available everywhere for $4


Ox-Gard Anti-Oxidant Compound contains prime grade zinc and is formulated with metallic zinc to create a compound that enhances electrical and thermal conductivity which is used on high power crimp connections and stud bolt mountings. When the connection is tightened, the grease is displaced, leaving a layer of zinc filling in the surface imperfections of the interface. This has a twofold effect; it improves electrical conductivity and it improves thermal conductivity. This reduces the connection temperature under high power conditions by a reduced voltage drop and by providing a heat conductivity path to the connection's substrate. Ox-Gard Anti-Oxidant Compound is manufactured with unique grease compounded from custom refined low sulphur oil. The grease base ensures brush-ability over a wide temperature range, tenacious adherence to all surfaces, resistance to water wash out and the prevention of rust and corrosion. This makes the product easier and more reliable to use.
  • Makes connections more reliable
  • Makes connections more weatherproof
  • Protects connections from corrosion
  • Reduces temperate rise
 
Last edited:

gm280

Supreme Mariner
Joined
Jun 26, 2011
Messages
14,585
Permatex makes a spray called Battery Protector and Sealer. You spray the connection after you tighten it up. It looks like a semi-transparent blue spray and kind of smells like a lacquer-based paint. It is suppose to stop battery terminal corrosion and seems to work pretty well. I am sure it would work to protect any connection from corrosion and moisture. And since it is a spray, simple to apply too. JMHO
 
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