How to use dielectric grease ?

The link
Originally Posted by kschachn
Originally Posted by ST2008
Hi

Can someone give me an official or a credible link regarding how to use the dielectric grease? I watched some video in Youtube and there are conflict messages. Some state that we should never apply the dielectric grease on the electrical connection. But other state the opposite.

thx

https://www.nyelubricants.com/stuff...ricating_electrical_connectors_final.pdf

Nye Lubricants knows what they are talking about and is a credible source. At one time someone posted a military study that said essentially the same thing but I can't find that post now.

The link just answers my question about using grease on computer pins. I have a Power Commander 5 that piggybacks the computer on my 2007 Harley Dyna and I was wondering whether or not I should use it on a multi pin plug in connector.
 
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Lolvoguy, I have the same problem with my 20 year old car's headlight socket connectors. Lights turn on if I wiggle the connectors but turn off again after a few minutes or an hour. Both high and low beams misbehave. I've sprayed electrical contact cleaner on the bare sockets but no joy. I've changed the headlight bulbs to no effect. I'm about to replace the socket connectors soon, but your experience has persuaded me to try dielectric grease too.
 
Go to the electrical supply house and buy some EJC . Or better yet , find a power company lineman and ask him for a cup full of whatever they use .
 
Ive heard anecdotal stories of dielectric grease reducing or preventing good contact. In some cases with thin, flimsy pins or something like that, I could kind of see it... But for most uses, I cant.

The actual contact surface in a connection is a small fraction of the actual surface area that is "touching". The Nye graphic shows it well. The use of the term "surface asperities" is correct.

For batteries, where the terminals are way spaced out, and there isnt particularly high voltage to begin with, I prefer a conductive electrical grease. I use NO-OX-ID. I apply it around the metal to plastic bases, and then a thin coating on the terminals themselves. Then Ill generally wipe a very thin coating on the upper exposed surface.

For any connector where there is the potential for potentials of different types in close proximity (such as in a harness), I like a thin coating of dielectric grease. I also like dielectric grease on the seals to help them avoid sticking.
 
I just replaced an electrical connector on my boat (a light pole base) where using grease in excess probably shortened the life of the part by blocking the drain hole at the bottom of the socket. My fault for sure; just be aware that you want the grease on the contacts, not necessarily the mechanical parts of the assembly.
 
Older car guy here.

A fuel filter's couplings accept smooth, shouldered pipes. I give these nipples a thin, thin wipe of dielectric or silicone grease.

I feel it's humane thing to do for the O ring or whatever the seal material is. It'll also facilitate future replacement.
 
Originally Posted by whosmatt
I just replaced an electrical connector on my boat (a light pole base) where using grease in excess probably shortened the life of the part by blocking the drain hole at the bottom of the socket. My fault for sure; just be aware that you want the grease on the contacts, not necessarily the mechanical parts of the assembly.



Those are notorious no matter what you do. Long term layup / water 🤦ðŸ»â€â™‚ï¸
 
I forgot to mention . Those lighting parts are pretty generic on boats. Most are off the shelf and made by Atwood . They're also fairly cheap so if your base is buggered up just get a new one. You can't really get at most of those recessed stern light sockets to clean them well or fix them. By the time you yank and pull them apart ect it's better to just swap for a new base and be done with it.
 
Originally Posted by Snagglefoot
"Over top" not "in between". Dielectric grease is an insulator. For use with batteries, make up the cable to the terminal and then put the grease over top. If you put the grease on the terminal and then put on the cable you run the risk of totally actually insulating one from the other. However, folks get away with it because like a previous poster said the grease might be "squeezed "out enough to still have a metal to metal connection.


Totally agree fully with this. It's how I use the grease myself. I always make sure I have what I'm working on together before adding the grease to seal out moisture. On spark plugs It's a little different being you can't add it after you have installed the wire to the plug so I put the grease inside the wire end and put it over the plug. Then I'll pull it off and wipe it off of the tip of the plug and re install. This way it's not to globed up on the contact point but is around the whole plug. Or if you can reach the plug easily wipe the grease around the plug itself without getting it on the tip. Then install the wire. Either way I try to keep my contact points dry.
 
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Yes it is an insulator but so is air. So if the contacts are not making contact, then contact won't be made no matter whether it is grease or air between them. The whole idea that it is an insulator is a spurious argument because it doesn't matter.

You either have metal-to-metal contact or you don't have contact at all. What the dielectric grease does it to fill the aspersions (just as the Nye link shows) and prevent subsequent corrosion, the products of which are generally of a lower density than the base metal. This causes the contacts to separate and disrupt current flow. So yes, you want the grease "in between" the joint as well as over the connection.

It also protects the non-contact areas from corrosion so that the next time you break and make the connection, those areas not previously in contact will be clean and able to make good contact this time.
 
Originally Posted by kschachn
Yes it is an insulator but so is air. So if the contacts are not making contact, then contact won't be made no matter whether it is grease or air between them. The whole idea that it is an insulator is a spurious argument because it doesn't matter.

You either have metal-to-metal contact or you don't have contact at all. What the dielectric grease does it to fill the aspersions (just as the Nye link shows) and prevent subsequent corrosion, the products of which are generally of a lower density than the base metal. This causes the contacts to separate and disrupt current flow. So yes, you want the grease "in between" the joint as well as over the connection.

It also protects the non-contact areas from corrosion so that the next time you break and make the connection, those areas not previously in contact will be clean and able to make good contact this time.


+1

If the dielectric grease "prevented" contact, there was another lingering issue already...
 
When I bought my truck, the trailer wiring harness / connector had dielectric grease inside it from the factory. The connector female holes were stuffed with grease.
In my other car, I cover both male and female pins with dielectric grease and never had any connectivity issues. If the contact points are making real/good contacts, the grease will be pushed away. It's not like the grease will be providing hydrodynamic lubrication :)

as far as battery terminals, I spray the CRC terminal protector stuff (red color) on top after they are connected and never had any issues.
 
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