Sabotaged myself: Dielectric grease is NOT conductive.

[capt_furious]

I've been having problems with the bullet connectors on my electronic ignition module corroding and causing the car to cut out. I cleaned the terminals, crimped the connectors a bit...

 

...and spread some dielectric grease on them.

 

Now, somewhere in the back of my mind I KNEW this stuff wasn't conductive, but I was convinced I was doing the right thing at the time. Hey, you put it on spark plug boots to prevent corrosion, right?

 

Yeah, you put it on SPARK PLUG BOOTS, not the metal connectors themselves.

 

I made it into work Monday morning, just as I'm pulling through the gate(Travis AFB), the car dies and refuses to restart. I leave the car in the nearest parking lot, hitch a ride, and get back to it in the evening.

 

Car ran fine back home. I took it for a spin a bit after fiddling with it, ran okay, so I took it to work the next day.

 

Same story...ran fine, then died. Got it restarted and it proceeded to run like crap.

 

I've been tearing away at it during the last two evenings, and I start looking for plug gap info, since I figured plugs might help - on the same page I find L28 plug gap info, I find a warning to not put dielectric grease on electrical connections because that's not what it was meant for.

 

BINGO! I'd put that stuff on all the contacts of the new dist. cap, on the plug wire connectors going into the cap, and on all of the pin and bullet connectors on the electronic ignition module.

 

About an hour of removing all of that crud with some carb cleaner, q-tips and an air compressor, the car runs GREAT. New cap, rotor, re-gapped distributor pickup, clean contacts, new ballast resistor, new plugs...I more or less gave it a tune up.

 

So, yeah. Use this stuff for what it was meant for. DON'T PUT IT ON ELECTRICAL CONNECTORS. Use it as a barrier against the elements to protect connections.

[jasper]

I've used Dielectric grease many times/many places/many years. NEVER had a problem.

You metioned cap,rotor etc.You changed many things at once.

How do you know the d grease was the culprit?

I use it on light bulbs, trailer connectors, etc,etc,etc,.

I don't thinkk the d grease was your problem.

 

A difinitive answer would be good for all..........

Edited March 4, 2010 by jasper

[capt_furious]

This has a pretty good amount of information: http://continuouswave.com/ubb/Forum6/HTML/001202.html

 

Essentially, it's for sealing connections, not improving them. The very definition of 'dielectric' is non-conductive.

[Daeron]

Learned this lesson myself, in a similar fashion. Oops!!

[cygnusx1]

I use it on all my connections.  Never had an issue.  Metal to metal contact is the best connection.  The grease should just surround the metal to metal contact point in a macro sense, to keep moisture and oxygen from oxidizing the contact.  Conductive grease is not the answer.  If your connections are tight, the grease will get displaced at the metal contact point, and do what it should do; surround it.  Odds are that you had some loose connectors in the first place.  Tighten them up if you can and try again. 

[Tony D]

I have always packed the entire connector, since my first underwater adventures offroading in the mid 70's. If you had a problem it was due to poor contact electrically metal-to-metal, and not because dielectric was in there. If you have a loose connection you will have problems, period. Dielectric spread over everything will keep ANY oxygen in the joint from causing ANY corrosion. It also precludes any moisture ingress. Any void left in the back shell of the connector is where the corrosion WILL start.

 

I pack the tower connections on the dissy cap, the boots in on the end of the plug wires...you just have to gauge it that you don't put too much in where it expands and pushes the connector off the plug!

 

I think this is a bit of anecdotal evidence that is misdiagnosing the root cause (poor tension on the connecting items) by blaming an incidental observed common link (the application of the dielectric grease).

 

I can take my lighting connectors apart that I greased up 10 and 15 years ago, and they look as clean as the day they were assembled, with grease still leaking out the backshells and all.

 

No water gets in there, no air gets in there, no green stuff forms there! Of course, they all has proper tension (disassembled and crimped back down with a small needle nose pliers) when gooped up.

 

It's exactly what Cygnus says: if you have good contact, the grease will be displaced at point of contact, and therefore preclude any foreign matter ingress. You can literally submerge the connectors in SALT WATER and you won't get a short from circuit to circuit if you have properly packed the connectors. I would drive my jeep IN the pacific ocean with the headlights on under water all the time in Japan. Of course then I had free access to Dow #4 from Uncle Sugar, and I used it liberally!

 

Were yours?

Edited March 4, 2010 by Tony D

[thrustnut]

We never used Dow 4 in the USAF while I was in (at least not that I knew of on 130's). I use it on everything as a civilian mechanic. Love the stuff and never had a problem with it.

[jasper]

Another very useful "chemical" is sold by Wurth. HS 2000.

This stuff is great. It is a colorless spray lubricant, that penetrates, and once the carrier has evaporated, leaves a tenacious, viscous lubricant behind. You can't beat this stuff(aka, the best) for hinges,pivots etc. GM has a version/private label equivelant of this stuff.

Go buy a can today..you'll love this sh*t!

 

 

http://www.paragon-products.com/product_p/wurth_hs2000.htm

 

One more thing, 3M strip caulk (don't substitute cheap crap). Go buy a box, you can mount speakers,stop vibrations,stick on trim,another thing you should not be without.

A blob sits on the top corner of my tool box. I use it every day. Holds bolts/nuts in sockets very nicely,and much more.

 

http://autobodystore.net/Merchant2/merchant.mvc?Screen=PROD&Product_Code=3M8578&Category_Code=JASS

 

3M Strip-Calk 08578 Black 20 yards (60 Feet) 1 foot lengths This black, non-hardening, paintable caulk is just the solution for sealing irregular areas in firewalls around heater and air conditioner boxes, lines and wiring harness connectors. Also great for rocker panels, trunks, around tail lights, trim and emblem holes or just about anywhere gaps need to be plugged. Effectively seals out water, dust, and dirt. Duplicates the caulking material used by many auto manufacturers. Made in USA

Edited March 6, 2010 by jasper

[thrustnut]

Anyone ever use this stuff called "fuel lube"? It's a supper thick sticky paste kind of stuff. We use it to seal fuel sending units that mount sideways in fuel cells. Also works great for holding nuts in sockets or sticking a nut to your finger when reaching back into places you can't see.

[srgunz]

We never used Dow 4 in the USAF while I was in (at least not that I knew of on 130's). I use it on everything as a civilian mechanic. Love the stuff and never had a problem with it.

 

 

When I was in the AF we did use the Dow Corning 4 on our F4's. Being in England wet aircraft was the norm. lol.

Also, you can buy conductive type connector lube as well. You want to be careful using it on multi-pin

connectors though.