How to use dielectric grease ?

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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
 
Dielectric grease locks out air and corrosion on electric contacts and connections. It should be used on any electric connection.
 
From the back of my CRC dielectric can >>>>>> Seals , lubricates, protects and insulates eletrical contacts ,spark plugs, battery terminals and fasteners from moisture. Lubricates and seals rubber and plastic parts-including O-rings. Waterproofs electrical contacts and components to protect against arcing due to moisture.
 
Where the electric connection is made, the grease gets squeezed out and you get metal-on-metal contact for good conductivity. Use dielectric grease for corrosion protection on battery terminals, screw-post connections etc. Also, use on the o-rings of sealed electric connectors and on spark plug boots. Since dielectric grease does not conduct electricity it helps prevent arcing and the leaking of current in the presence of moisture.
 
Originally Posted by vavavroom
Where the electric connection is made, the grease gets squeezed out and you get metal-on-metal contact for good conductivity. Use dielectric grease for corrosion protection on battery terminals, screw-post connections etc. Also, use on the o-rings of sealed electric connectors and on spark plug boots. Since dielectric grease does not conduct electricity it helps prevent arcing and the leaking of current in the presence of moisture.


What he said.

BSW
 
"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.
 
I used some self leveling Dow silicone grease once on my battery terminals. It creeps and gravity will pull it down. Put it on top of my cables and after a month I stated having starting issues due to the insulating by the grease between post and cable.

But the last three cars I have not used any grease on the terminals.

If you have corrosion you have a leaking battery.
 
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Originally Posted by Snagglefoot
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.

I found out the hard way not to use dielectric grease in between the battery post and the cable terminal. Tractor wouldn't start and when I tried all I heard was a big spark because the grease hadn't been squeezed out enough. Ended up cleaning everything up with brake clean.
 
I too have been confused by this subject. Dielectric grease will prevent good electrical contact if any gets into the posts or wires. While it may seal out shorts it should not get into the wires so I only use it on my power equipment spark plug boots, NOT the spark plug itself.
I had to clean up several flashlights that went berzerk after using dielectric grease.
 
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.

A common notion but incorrect.Yes dielectric grease as such does not conduct electricity but it doesn't matter. You don't want electricity flowing between gaps in conductors anyway, the grease does not inhibit conduction where metal-to-metal contact occurs. This subject comes up on here from time to time and there are studies you can find which show that using dielectric grease inside a connector does not impede current flow. If the contacts aren't making contact, then you aren't getting current anyway unless it is arcing.

You're not "getting away" with anything. If the connection isn't tight then the presence of grease or no grease isn't going to matter.
 
For me dielectric grease is nothing more than a non-conductive (for automotive applications) grease that seals out moisture from electrical connections, preventing corrosion. Since it is non-conductive, if it doesn't squeeze out and ends up in between the connection, then it causes more problems that what it's fixing. That is where I think most of the conflicting information comes from is how successful it works for each individual. This is definitely one of those cases where a little goes a long way.
 
Again, if the contacts aren't making contact then that's your real problem, not the dielectric grease. If they are making contact then the grease is not the problem either.

And before someone suggests it, conductive grease is NOT what you want.
 
Originally Posted by kschachn
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.

A common notion but incorrect.Yes dielectric grease as such does not conduct electricity but it doesn't matter. You don't want electricity flowing between gaps in conductors anyway, the grease does not inhibit conduction where metal-to-metal contact occurs. This subject comes up on here from time to time and there are studies you can find which show that using dielectric grease inside a connector does not impede current flow. If the contacts aren't making contact, then you aren't getting current anyway unless it is arcing.

You're not "getting away" with anything. If the connection isn't tight then the presence of grease or no grease isn't going to matter.

My experience is my old cable terminals are not the same exact size (larger) as the battery post leading to inconsistencies in how well it makes contact and therefore squeezing the grease out. Before I go and replace my terminals I'll continue using the oil soaked felt pads.
 
Originally Posted by SVTCobra
My experience is my old cable terminals are not the same exact size (larger) as the battery post leading to inconsistencies in how well it makes contact and therefore squeezing the grease out. Before I go and replace my terminals I'll continue using the oil soaked felt pads.

That could be true. But if they aren't making contact then they aren't making contact. Air is a dielectric as well.
 
It's making good enough contact to work without the grease, hence why I said I don't use it on battery terminals from my post about the tractor.
 
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.
 
Originally Posted by kschachn
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.

A common notion but incorrect.Yes dielectric grease as such does not conduct electricity but it doesn't matter. You don't want electricity flowing between gaps in conductors anyway, the grease does not inhibit conduction where metal-to-metal contact occurs. This subject comes up on here from time to time and there are studies you can find which show that using dielectric grease inside a connector does not impede current flow. If the contacts aren't making contact, then you aren't getting current anyway unless it is arcing.

You're not "getting away" with anything. If the connection isn't tight then the presence of grease or no grease isn't going to matter.

I respectfully disagree (or maybe I'm agreeing?)

On the e30 in my sig below my drivers side fog light would always flicker. Been this way since I bought the car 16 years ago.
The bulb (incandescent) was fine, but only when I played with the wiring harness behind the light, did the bulb illuminate.
I was convinced the only way to fix this problem was by getting a new harness to plug into the back of the light, as the contacts on both the harness and light were showing signs of corrosion.

On a whim (maybe it was laziness) I tried slathering some dielectric grease into the light housing socket.
Sure enough when I went to try it again, the light worked flawlessly (no more flickering).

coffee2.gif
 
Besides the anti-friction (lube) properties and reconditioning it can do to compatible materials, dielectric grease is used for protection, to seal against water and air, when contacts are exposed rather than completely sealed away from the elements, in conditions that contribute to corrosion.

It "can" create a worse contact initially (particularly in situations with large planar contact at low force per area), but time and pressure (combined with no more than moderate viscosity) result in fair electric conduction and more importantly it greatly decreases exposure to air and water, or other misc vapors or dust/etc contamination.

The question is somewhat backwards. You don't grab dielectric grease and ask how to to use it. You use it in an application that benefits from it.
 
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