The primary purposes of dielectric grease are to keep out moisture and prevent corrosion. The prevention of corrosion keeps the metal-to-metal contact point in a connector conducting electricity. If the grease conducted electricity, it would allow the tracking to the ground of the power or signal is conducted.
It’s neutral and forms an excellent 02 block. Also lubricates but w/o any specific bulk. Won’t’ work for heavy-loaded bearings, etc. Great for multiple plug blocks, relay contacts, slide contact switches, rubber lube, speedo cables when combined w/graphite, etc.
In addition, it is used for a heat conductor when some electronic components are mounted on surfaces to dissipate heat (like the ignition power stage on coils).
It is non-conductive, but when you slide the connectors together there is metal-to-metal contact and the grease gets displaced but the area around the connector is protected from moisture.
If the grease was conductive it would be too easy to get “bleed” from one pin to another in a connector if the grease got hot and liquified and spread.
DO NOT ever grease an oxygen sensor connector as the sensor is vented through the wiring on many sensors and the grease will contaminate the sensor over time and it will cease to function.
It helps keep the contact clean. Dielectric grease can be used to improve conductivity in bullet and spade connectors while protecting the joints from exposure to moisture, dirt, acid, what-have-you. Check the local auto supply. http://www.vectorbd.com/peugeot/archive/General/2004/Mar/0265.html
Not sure how many of you already use Di-Electric Grease, but it occurred to me that some might like this tip. I was doing some preventative maintenance on some of my “toys” when a neighbor came up. He saw me using Di-Electric grease and asked me about it. I use it (CRC Technical Grade DI-Electric grease) on about everything electrical.
I fill the sockets when replacing bulbs on vehicles and on OUTDOOR 110-volt lights fixtures (floodlights, etc) I put a good coating on the bulb threads prior to insertion to prevent water intrusion and corrosion.
I also fill the sockets and coat the male ends on any trailer or TOAD connections.
I also recently replaced my cellular and CB antenna and coated all the exterior threads and connections prior to assembly. Another great use is on all shore power connections. I coat the pins and the female side of my shore tie plug at the coach end and also coat the blades of the 50 amp plug before inserting it into a plug. The coating on the Shore Tie coach end lasts for about a year. I keep a container of the grease in the utility bay to remind me when hooking up power. I use it on any 50-30-15 amp adapters that I use. It really improves the connection and prevents corrosion.
This grease also works great to “lubricate” the fuel tank filler cap o-ring on any vehicle. I use it on all my vehicles with spark plugs to fill the spark plug cap before putting it on the plug, it improves the connection, seals out moisture, and ensures that the plug wire will not seize to the plug.
This grease works great to coat new filter o-rings and seals prior to installing the new filter. Greg & Cheryl 1995 280 SE