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My 1994 940 wagon has some suspect earth points at the rear - I get an intermittent bulb failure warning light when the rear heater is used and I push on the brakes, or it just comes on after a period of time anyway but goes away when window heater turned off. I want to do the earth point cleanup job in the next few weeks.
I understand that when cleaning up an earth point, it is a good idea to use a conductive grease. I'm having difficulty getting this stuff, and the only place I found with some stuff that looked suitable had it avail in a 865g tin for circa US$75 (NZ$118). (They were an electrical wholesaler and weren't interested in carrying the smaller qtys) Here's the manufacturer's webpage.
http://www.cramolin.de/konten.htm
Can anyone recommend other brands of conductive grease that I could hunt around for, ideally stuff that is available in a tube ?
Note: It's definitely CONDUCTIVE grease that I want. I already have some of the dielectric (insulating) stuff for other electrical connections, and this conductive stuff I would ONLY be using on earth points.
John Marshall
1994 940GL
Christchurch NZ
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John,
Might be just a fine point, but you never know what a term like "conductive grease" might do to raise eyebrows when you go asking about.
Ox-gard doesn't conduct electricity any better than "dielectric grease". Yet silicone (dielectric) grease is used to aid in the conduction of heat.
Now that you're fully confused...the grease you are looking for keeps the contact between dissimilar metals from getting air. Mostly it is sold in the electrician's section for making terminations with aluminum. Maybe we should call it the electrical anti-oxidant.
Anyhow, I believe a 100g tube is seriously less than US$10. and common. But maybe your electrical code is smarter than ours and does not allow aluminum wiring indoors.
Oops - I see Steve has already explained :-)
--
Art Benstein near Baltimore
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Art,
Lord knows I'm no electrical engineer... but my tube of Ox-Gard says it's a conductive grease that prevents oxidation. Doesn't that mean it conducts electricity?
Thanks in advance for your input.
Jeff Pierce
--
'93 945 Turbo ( one kickass family car ! ), '92 Mercedes 190E (my daily driver), '53 Willys-Overland Pickup (my snow-plow truck/conversation piece -- sold to a loving home), '85 Jeep CJ-7 w/ Fisher plow
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posted by
someone claiming to be art
on
Tue Sep 28 08:00 CST 2004 [ RELATED]
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Jeff,
Now that just goes to show you what a lousy reader I am. I never read my tube of Ox-Gard. If the maker says it does, then, it must.
Here's my excuse for claiming it doesn't:
I checked a dab of it with my ohm meter. On the highest scale-- you know, where you can get a good reading from the dry skin on the back of your hands, say 50 megohms? Pushing the probes toward each other through the dab of grease
I had to actually touch them before getting any response on the meter.
But I'm sure it aids conduction.
Just thought it did so by preventing oxidizing film.
And now I hope someone will explain it all to me.
Maybe the conductivity is confined to small particles in suspension that are insulated by the grease until under pressure of contacts.
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I bet you're right, that any conduction that's happening is at a microscopic level (perhaps even on a molecular level). From the term "conductive", I assumed that there would have been continuity in the test you performed -- but that's clearly not the case.
Thanks for sharing the results of your test.
Jeff Pierce
--
'93 945 Turbo ( one kickass family car ! ), '92 Mercedes 190E (my daily driver), '53 Willys-Overland Pickup (my snow-plow truck/conversation piece -- sold to a loving home), '85 Jeep CJ-7 w/ Fisher plow
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posted by
someone claiming to be art
on
Wed Sep 29 06:29 CST 2004 [ RELATED]
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Jeff,
<humor>
I put the ohm meter probes into a dollop of copper anti-seize without getting a response. So my "conductivity" test may not be the best one to use when deciding whether to fill your multi-circuit ECU or AMM connector housing to exclude moisture. As horrifying as it sounds, I bet it would survive just fine at low voltages. Maybe not a good idea on the distributor cap...
</humor>
Also took a moment to read my copy of the tube of OX-400. Says "increases conductivity" and I bet all that zinc just fills in between the aluminum and copper where it doesn't make solid contact. The tube is marked AL-AL and AL-CU, so I don't know if there are other versions of their product.
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Art, would you please explain why you said that "Ox-gard doesn't conduct electricity any better than "dielectric grease"."?
I thought that it was stuffed full of Zinc. Makes it gray. Is the zinc conductive? Must be. (Ha! Most EVERYTHING is conductive, to some degree... but we don't, for instance, gold plate or silver plate most electrical connections, because of cost.)
Or does the Zinc volunteer to sacrifice itself, as needed, as in galvinizing?
Thanks!
--
Gregg; Mpls, MN; 1987 745, 1967 Amazon 4-dr.
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posted by
someone claiming to be art
on
Tue Sep 28 08:25 CST 2004 [ RELATED]
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Gregg,
I messed up and didn't read the package. Just stuck my meter probes into it. Perhaps it is conductive once the connection squeezes all the grease out of the way- the zinc that is. Two weeks ago I was taken to task by my brother in law for using the term "sacrificial anode" at the dinner table. He lives on a lake, but more of a flyer than boater.
But I really figured someone would question whether Ox-Gard had as much dielectric strength as silicone grease...
Next project: Spray a teaspoon's worth of Zinc-It in a bottle cap and test it for conductivity. Break out the Hi-Pot!
Good to see you writing again, Gregg.
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Aw, Art, your brother-in-law needs to get with it! ("I was taken to task by my brother in law for using the term 'sacrificial anode' at the dinner table. He lives on a lake...")
Fill him in (and drive him nuts).
Lakers need Magnesium sacrificial anodes, not Zinc, as mariners take.
The steel rudder on my sailboat is pitted, I see now, and my Yamaha outboard is suspect... and I NEED MAGNESIUM!
AND the sacificial Mg anode in my water heater (Rheem) refuses to come out, despite pblaster, banging, etc.
Going to a GOOD plumbing supply shop is high on my list. Gotta have Mg.
OR getting to know a high school chem teacher?
And, like you say, when I fix this stuff, I will "break out the Hi-Pot!" Pfffft! (Aw, just kidding... I can't take that stuff no more.)
--
Gregg; Mpls, MN; 1987 745, 1967 Amazon 4-dr.
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Art
thanks for the clarification regarding "conductive" grease.
I've never come across aluminium wire for domestic use - it's all copper in NZ, which is maybe why stuff like Oxgard is just not found in local hardware stores and building merchants here ...
John Marshall
1994 940GL wagon, 163,000km
Christchurch NZ
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John, if you clean off your grounds, then coat them with silicone dielectric grease, you'll be fine. The point of the OxGard is to both conduct better and prevent oxidation. The silicone will do the latter and not affect the former. The conductive grease is marginally better in situations in which circuit isolation is not an issue, as with ground planes.
You are lucky there is no aluminum house wire in NZ, as many burnt house owners and fire departments in the US can attest. Another "breakthrough" gone awry.
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Go to a home improvement store with a good electrical department. They have it for use in electrical wiring, especially where aluminum wiring is used. In the US, the brand is called OxGard (for "oxidation guard") and is commonly found in Home Depots, etc. Comes in a small tube for about US$2.00
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Sure, they have it here http://www.ehobbytools.com/index.html?target=p_458.html&lang=en-us good luck!
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