Dielectric Grease - Uses?

Marcus

Marcus

Well-known member
Gentlemen: I confess that I am totally confused (not surprising to some gentle readers, I am certain)! One poster has indicated that dielectric grease should be liberally applied to all electrical connectors, to include inside the battery cable ends and over the terminals. Another indicates to never coat the terminals. Someone with knowledge please weigh in and make an absolute statement? (By the way, the website indicates to cover everything....no help there.)
 
Somewhat like asking your favorite color or the best oil, etc. Dielectric grease is just what it's name implies, it blocks electrical current. BUT, in most applications this is somewhat irrelevant as a tight connection squeezes the grease out and you get metal to metal contact. I use a lot of dielectric grease for things like multi-pin connectors or plug wire boots where it is doing what it is intended to do, protect and block electrical current. To me something like a single connection or a ground is better served with a protective coating that is conductive. I am currently using NO-OX-ID and like it (but this is a short term usage to date!).

IF you have good clean mating surfaces AND contact metal to metal AND squeeze the dielectric grease out of the mating surfaces, it should work fine. But it just makes more sense to me to use a protective coating that does conduct.
 

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Dielectric grease does not conduct electricity but may be a bit strong to say that it "blocks" electricity. That suggests that it is an insulator. That, of course, would not make any sense to coat electrical connections with prior to connection.

The reason I use it on all electrical connections is to prevent corrosion. It does that best. It keeps moisture out of the connections that keeps those little corrosive crystals from growing between the connections and eventually breaking the connections. It also makes disconnecting a little easier when time to unplug.

The problem I see with using electrical conductive grease, particularly on multi-pin plugs, is, if there is any slop between the pins, that's going to be a short. Too risky for me.
 
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Old Henry it is an insulator and it does "block" electricity, that is it's function. That is why you can put it in multi-pin connections with pins very close together. It keeps moisture out and totally blocks any current flow between sensitive pins. It is what is used in multi-pin connectors on computer connectors. It is so good at insulating that it helps block even high voltage in a spark plug boot.
 
This is s subject I have wondered about many times. Living on an island surrounded by salt water in an already wet area, we fight corrosion on a daily basis. I'm gonna go warm up the microwave for some popcorn.
 
Yep, those articles have been around for a long time. Like I said in my first post, if you like dielectric grease use it, doubt it make much difference 99.9% of the time (maybe 100% :)). I prefer a different approach, but I'm not running for office and not attempting to sway anyone.

Using dielectric grease seems to be a religious issue to some folks, no idea what the emotional element is. But, if that is your religious bent, LOL
 
Blocks electricity is hard for some to understand. It more or less helps isolate and insulate IE. Puts a protective coating on a connection. It stops moister and corrosion. It will not "block" electricity when applied to a metal on metal connection. It will help stop a spark jump from connections that are very close to each other. It also helps keep connections from getting hot from over load. At least that's what iv been told from an ol wise man.
 
I have been using it since the early 70's when Ford introduced their electronic ignition? They required its use on all ignition connections when servicing or replacing parts. It proved invaluable in humid or salt air climates in preventing corrosion. Current flowed through connectors without problem and water and water vapor could not cause problems. We worked on Nissans/Datsuns. They would be shipped by boat, spending weeks or months at sea or sitting in lots in sea ports. Their connectors would corrode and cause problems down the line. They would developed what we called "sudden curb death syndrome" and refuse to start. We would take each of the connectors apart, clean the corrosion and reassemble them using dielectric grease. Boom, problem solved! I keep saying tube in my tool box, even though in retirement it gets used far less, I still use it on all connections to this day. I know this is long winded but I felt it necessary to share. I convinced my son the mechanic, and he uses it to even when he changes light bulbs.
 
The primary function of these protectants is to provide a coating to help prevent corrosion and block moisture. When using them be sure you understand which application is appropriate for each. A non-insolating protectant should only be used on single path connections, such as battery terminals, grounds, connections between two connectors, etc. In multiple path connections or where an insulating property is required only a insulating protectant should be used! Examples would be any multi-pin connector, light bulb socket, spark plug boot, etc. If it is not clear to you what is going on between insolating and non-insolating protectants stick with the insolating! An insolating protectant will work in any application as long as there is good metal to metal contact, however using a non-insolating protectant in the wrong application will cause issues. Examples would be a light socket where it would short a two filament bulb terminals or short the terminals to ground. Likewise on a spark plug boot it would short the high voltage spark to ground through the boot. So be sure you understand what is going on if you want to venture into these areas!
 
For battery cables and ends, clean with Coke-A-Cola and coat with Vaseline. Has worked wonders for years on our daily drivers. Simple and something everyone has in the homes!!! DONE
 
Use of dielectric or silicon based grease began in the aircraft industry many years ago and has filtered into the automotive world with little or no explanation of its uses. It's this lack of understanding that causes the contention for its use. The basic purpose has already been mentioned in this thread so I won't get into that. The most common use I've seen it called out for in automotive use is for the modern one coil one per spark plug ignition systems that are in wide use today. It will definitely prevent arcing over of high tension voltage between the coil and the spark plug. Even with a rubber boot in place, a high voltage can still find a pathway for arcing to the nearest ground path. Use of the dielectric grease is very necessary to prevent this arcing over.
 
Instead of saying that dielectric grease blocks electricity it might be better for some to understand that it does not conduct electrical current. Therefore it is safe to use for lube, corrosion protection etc. without shorting to adjacent circuits or grounds.

Peteva
 
Very interesting and informative answers, Gentlemen - Thank you! My overarching concern was that, by coating the battery terminals and then installing the cables, I was causing unnecessary strain on the starter by reducing available voltage. Inasmuch as this appears to not be the case, but also that the general opinion is to only apply a "covering coat" after installation, that will be my choice.
 
I started down this road by using wheel bearing grease on the battery terminals about 40+ years ago, switched to silicone-based greases in the late sixties. I wouldn't put a parking light bulb in an old car without the grease. These old Fords are subject to moisture entering through the wiring harness/socket boot area at the rear of the housing.......Bob L
 
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