Rusted Spade Plug Connections

Sand paper works well for cleaning, but don't forget to give the female connectors a clean to as they are probably corroded also (a simple case of making and breaking the connection a few times to wear the corrosion off).

What environment are the appliances in to get so corroded?

Are they near the sea and the corrosion is salt air based?

ususally in ac units, refrigerators exposed to the weather, bbq iginters, ect

i'm working on a grarden tractor. all the electrcal connects are so badly rusted that i've been considering painting them with sulfuric acid then neutraling them with baking soda.

Muriatic acid works well too...aftewards I neutralize with water (distilled if you have it). Then heat to dry quickly and coat with dielectric grease or terminal protector spray.

I agree on this response. Replace the connector.

If there is not enough play, solder on an extension wire (a few inches), shrink wrap the solder joint, and crimp on another connector.

Might seem like a little much at first, but a couple of goes and you will swear by it.

GA Kramarat.

i use these type of connectors all the time,but only for light duty work. they're worhless for the most part. . i remove the plastic and solder the wire to the terminal end the use heat shink tubing to make them water tight.

If it's a spade connector originally, it's usually light duty.

i'm also working on a 15 amp ac unit with dozens of rusted spade connectors. what a b#tch it is.

If you replace the spade connectors, you can then spray them (after they're in place) with clear plastic spray. It will waterproof them and eliminate further rusting.

I have a John Deere tractor and have sprayed all of my wire connections, relays, etc.

Unfortunately this collection does not illustrate the heat shrinkable water proof connectors used by trailer builders and marine electricians.

A minor point is these connectors are not rated for more than 10 amps unless special high current connectors are used. Also use either T&B ir Burndy brand for best results. Panduit sometimes make thin metal fittings that over heat at 10 amps.

I just threw up a random picture of new connectors to illustrate my point.

If I'm ever redoing anything, I typically throw away the cheap stuff and get the best replacements available.

The illustration is good as far as it goes. Unfortunately most people do not encounter the sealable types in normal work. The one poster who removes the existing plastic sleeves then heat shrinks a sleeve comes closest to a good solution. There are two kinds of heat shrink sleeves. The kind you most often find in automotive electrical supplies whoch lacks a heat activated sealant, and the kind normally ordered from the manufacturers. this kind has a adhesive liner that melts with heat and conformally seals the connections. I worked as an underground cablesplicer and used the adhesively lined type from Raychem. Even five years later not one splice leaked and failed; more a testimony to the technique and product selection than to anything else. Product use and assembly method is clearly given from the manufacturer.

The acid's already there. Just brush a strong solution of baking soda and water on the lugs and watch it bubble.

Rinse and repeat, as necessary.

Rust has acid in it? I've used that method on corroded battery terminals............................never tried it on rusted connections.

Perhaps I jumped to a conclusion that his "rust" might be my "corrosion" with rust.

If it's really rust, spray the crap outa it with UU:D-40 and let it sit for a day.

What do I know? I'm just an old crow, remember?

corroded battery connections are a result of acidic gases from the altenator charging the battery. i pour baking soda mixed in hot water over the terminals after cleaning them. repeat until the mixture stops foaming. rinse with water. grease the battery terminals posts and clamps with grease or buy a product designed for this purpose at the auto parts.

Worth a try. After drying it off, it wouldn't hurt to hit them with some dielectric grease before hooking back up.

http://www.loctiteproducts.com/p/s_trmt_naval/directions/Loctite-Naval-Jelly-Rust-Dissolver.htm

kramarat,

GA,

Naval Jelly should fix the rust! Provided that there is any metal left afterwards!

Sleepy

If you have real rust, i.e. reddish brown, that means you have steel electrical connectors. Steel connectors are used only in the cheapest of cheap crap. You should not be repairing that crap, you should be replacing it. The reason why they call those things "definite purpose" is because all of the components are made as cheaply as possible and are not designed to last beyond the weakest link. So since no part of it was ever meant to be repaired, repairing it means you are moving the next point of failure to another component, that one might be much more catastrophic.

If on the other hand you have greenish corrosion, that is oxidized copper, usually copper sulfate. As mentioned, that is ALREADY the result of an acidic reaction (think acid rain) and a good thorough cleaning with a basic solution, like baking soda and water, would be good. Then spray it down afterward with a good electrical contact cleaner to get rid of the water. WD-40 is a water SEPARATOR, but not a good remover. You want the kind that almost instantly evaporates and takes the water with it. A spritz of WD-40 after you are all done is not a bad idea though, it offers some limited protection for a while.

all the connection i've seen are metal to metal. i've never seen a the manufacturer use a rust preventative or dielectric even on expensive equipment.

i've never seen a the manufacturer use a rust preventative or dielectric even on expensive equipment

Why should they? Everything is new. They only have to keep it that way until they sell it.

"is there a simple solution?"

No.

If you're going to reuse the old connectors, this might be another option. I've got one and they make quick work of cleaning up metal. Especially small jobs. You just need a compressor and a bag of sand from home depot or somewhere.

http://www.northerntool.com/shop/tools/product_23137_23137

There are a lot of good ideas in the responses so far, some are rather difficult to implement and some will last only a short time. I work with expensive instruments that also have corrosion issues.

I have spoken to many metallurgical chemists for a solution to this problem. The general consensus from them is: Once the metal has started a corrosive process, it will continue at that point in its microstructure to 'grow' corrosive salts that are impossible to remove completely with any chemical wash, as they are etched into the microstructure of the metal, and what is left behind provides a kind of a seed that will continue to want to grow. The only way to stop the corrosion once it has started is to remove the layer of metal that has started to corrode.

Next, you have to decide what you want to do that will provide good value for your effort. If the machinery is worthy of a long life other than the electrical contact issue, the best solution is to eliminate the mechanical connections (spade). To do this, of course, you would be cutting off the wire's connector and soldering it to the cleaned up terminal on the part (It has to be clean, bare metal in just a large enough area to make a solder connection to the wire. The sand blaster idea has some appeal, if it will not do damage to other areas, I have not tried it, and it might be quite difficult to get set up for field repairs.) For most applications, it will not be necessary to have the traditional hole in the terminal for the wire to go through, just 'tin' both parts of the connection with electrical solder (a little extra liquid or wax electrical flux might be helpful) and join them with a smooth (shiny) solder connection, and your problem is now solved. You can cover the connection with a coating or heat shrink, but this does little more for you than provide safety from fingers in the wrong place gettin a shock. The soldered connection will now last far beyond the other metals as far as corrosion. I have seen where the wires and terminals are mostly eaten away, and the only thing left in tact was the solder at the joint. For some reason, the other metals seem to get corroded away much quicker.

I understand that now, after your soldered repair (design upgrade), when a part needs to be replaced, it will need to be soldered into place, but that is the price you pay for reliability and a good reputation for your technical work.

When you identified the corrosion problem, you were really identifying a design issue. We have traded reliability for speed of assembly here. The spade connectors were designed not for improved quality of product or reliability, but to save money on production and repair labor. Since you care about reliability and longetivity, and maybe conservation of resources and what not (thank you), your next step, if the customer can aford it, and the product is worthy of it, you can do this and build a good reputation for yourself, and a lot of grateful customers.

It is my personal opinion that this process can be done fairly quickly as long as an effective method is used to keep track of the many wires, and where they will have to be returned to. (Key point, trust me!)

Good luck!

In my experience the female part suffers deep corrosion due the tight bend on the left and right side. It then does not clamp properly. Only replacement help. Anticorrosion paste or wax spray or melt extend the contacts life beyond you care. Even if the spade has to remain as-is. I got up to 10 years with weather exposed connectors.

The sad thing is they use these poor connectors on the grounds in automobiles too.

Chased a problem for a year where the engine would just die and some random time later it would restart and maybe drive OK for a month and do it again.

Turned out that all the engine grounds were returned to the firewall where a daisy flower-looking double disk of male connectors was rusty. Cleaned it all up and never had another problem. I just sealed the contacts with Silicon Grease.

The dealer almost had me talked into buying a new computer at $2500.

Where it is difficult to get sandpaper in, uses emery board - the type women use for filing nails. Also remember that if the spade is corroded, the wire it is crimped to will be deteriorating too. This is often the actual cause of the bad connection and no amount of cleaning of the spade will make a decent circuit.

There is no such thing as filing or sanding a connector without destroying it. They are precision made parts and will be destroyed.

The wire is usually damaged also when teh connector is toast.

Cut the wire back to where its clean copper and start over.

This is not true for many (if not most) connectors of this type as there is a certain amount of spring and tension in the female socket (by its very design) to account for the reduction of thickness of a few tenths of a millimeter.

I've dealt with thousands of these.. most often in outdoor and moisture prone environments. The only simple solution is to pull the connection apart and give each side of the female connector a gentle squeeze as well as spray on a little dielectric lube as suggested.. It works like a charm.. oftentimes it's better than the original connection.. If there's any play? Squeeze away..

This is not an endorsement but would something like this work for you? It works as advertized on metal(I've used it)

www.rustremover.net

Again this is NOT an endorsement