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Posted

I'm sure that Wayne wouldn't mind me spreading the word.  :P: '

 

 

Using Dielectric Grease on connectors.

A lot of people use dielectric grease on connectors. Some people mistakenly believe that dielectric grease is a conductor. In fact, it is just the opposite. It is an insulator, and a good one. That is the basic definition of dielectric, an insulator. Dielectric grease is typically made of silicone grease.

As an insulator, dielectric grease is good for use on spark plug boots. This was one of the original applications on vehicles when the high energy ignition systems came out. It can help insulate the connector, and in particular on a motorcycle where it can get wet, it waterproofs the spark plug boot. And because it is silicone, it is fairly stable at high temperatures and won’t affect the rubber and plastics.

So why would you put an insulator on a connector? The idea is that you use a thin layer. When you push the connector together, the grease is pushed out of the way enough to get a connection, and the surrounding grease then keeps out water and oxygen. The connector will be protected from the environment, and less likely to corrode. Plus the silicone is safe for the plastics and PVC insulation.

That sounds good, so far. 

So why not smear it on everything? Well, there are a number of reasons.

1) Silicone grease outgases constantly. If the silicone gas gets near a connector or a contact such as a relay, and there is any arcing, the spark at the contact can create silicon dioxide. Some companies even suggest that the silicone gas from dielectric grease can travel many feet through the insulation on a wire and damage a contact on the other end. Omron states that even their sealed switches can be damaged by nearby silicone grease out gassing. Reference below for more info.

2) It is an insulator. It can prevent contacts from touching. If you must use it, use a very thin layer.

3) If you have a corroded connection, silicone grease will not help. In fact, it can only make a connection worse. It can never improve anything. Dielectric grease will never make a poor connection better.

4) It attracts dust and dirt and it due to the out gassing, it hardens over time. 

This means that if you smear a lot of silicone grease on connectors, you may see nearby relays, switches or points fail later on. And since the silicone grease does nothing at all to improve the connection, and in fact may insulate the contacts in the connector increasing the resistance, the connector may still fail.

So what do you do? Look for a contact enhancer/lube. While most contact cleaners are simple solvents that just wash the connector off. There are contact enhancers that deoxidize the contact surface and actually work to lower the contact resistance (make a better connection). Most contact enhancers leave a lubricant behind that protects the metal and continue to deoxidize the metal and improve the connection. They can work to lower the resistance and actually make a BETTER contact as time goes by. The best you can hope for from dielectric grease is that it seals it enough to not get much worse. I have used Caig Deoxit on my bikes for a few years now. I first found out about this on my job when I had to correct an issue in a scale load cell connector system that could not tolerate even 5 thousandths of an ohm of resistance drift. We had a connector in the field that had been improperly plated and was starting to drift, mostly in warm humid areas like Florida. Our testing showed that the Caig Deoxit could be a good long term fix. We ended up using the Deoxit to stabilize the bad units until we could get corrected wiring harnesses built with the correct connectors.  We also put a layer of Deoxit on the new parts to protect and keep them clean over their lifetime. This totally solved the resistance drift issue that we had. Our information on this product showed that the contact would actually get better for a period of over 1 year. The resistance would then begin to deteriorate, but at a much slower rate that a connector without the Deoxit. 

I still use a small amount of silicone grease on my spark plug caps. It helps to waterproof them and makes it easier to pull the cap off. (have you pulled a plug cap on a Stelvio yet?) But I use it in very small amounts and never near a relay or switch. 

Useful links:

1)      http://www.ia.omron.com/product/cautions/30/precautions_for_correct_use.html

2)      http://machinedesign.com/article/lubricating-electrical-switches-1025

3)      http://www.echeloninc.com/contactlubrication.htm

 

Wayne Orwig

 
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Posted

My story. I'd bought a Strada that hadn't run in years. A previous owner had decided that di-electric grease was a good idea, and filled every nook and cranny of every electrical connector on that bike with it. Naturally, it never ran again. :homer: Another guy bought it, and never got it running. I bought it from him, saw the di-electric grease in *everything*, and cleaned it out. The previous owner had even bought a new Digiplex unit.. $$ to no avail. It started right up, and I was patting myself on the back. Took it for a ride, thinking, "cool scooter" when it quit. That was the first of about 5 times I was standing beside the road. Apparently, when it go hot enough, the grease would migrate down the wires and cause an open connection somewhere. It's apparently ok, now, but I don't want it anywhere (except on the spark plug boot) on my bike. YMMV, of course.. :oldgit:

Posted

I'm sure that Wayne wouldn't mind me spreading the word.  :P: '

 

 

Using Dielectric Grease on connectors.

A lot of people use dielectric grease on connectors. Some people mistakenly believe that dielectric grease is a conductor. In fact, it is just the opposite. It is an insulator, and a good one. That is the basic definition of dielectric, an insulator. Dielectric grease is typically made of silicone grease.

As an insulator, dielectric grease is good for use on spark plug boots. This was one of the original applications on vehicles when the high energy ignition systems came out. It can help insulate the connector, and in particular on a motorcycle where it can get wet, it waterproofs the spark plug boot. And because it is silicone, it is fairly stable at high temperatures and won’t affect the rubber and plastics.

So why would you put an insulator on a connector? The idea is that you use a thin layer. When you push the connector together, the grease is pushed out of the way enough to get a connection, and the surrounding grease then keeps out water and oxygen. The connector will be protected from the environment, and less likely to corrode. Plus the silicone is safe for the plastics and PVC insulation.

That sounds good, so far. 

So why not smear it on everything? Well, there are a number of reasons.

1) Silicone grease outgases constantly. If the silicone gas gets near a connector or a contact such as a relay, and there is any arcing, the spark at the contact can create silicon dioxide. Some companies even suggest that the silicone gas from dielectric grease can travel many feet through the insulation on a wire and damage a contact on the other end. Omron states that even their sealed switches can be damaged by nearby silicone grease out gassing. Reference below for more info.

2) It is an insulator. It can prevent contacts from touching. If you must use it, use a very thin layer.

3) If you have a corroded connection, silicone grease will not help. In fact, it can only make a connection worse. It can never improve anything. Dielectric grease will never make a poor connection better.

4) It attracts dust and dirt and it due to the out gassing, it hardens over time. 

This means that if you smear a lot of silicone grease on connectors, you may see nearby relays, switches or points fail later on. And since the silicone grease does nothing at all to improve the connection, and in fact may insulate the contacts in the connector increasing the resistance, the connector may still fail.

So what do you do? Look for a contact enhancer/lube. While most contact cleaners are simple solvents that just wash the connector off. There are contact enhancers that deoxidize the contact surface and actually work to lower the contact resistance (make a better connection). Most contact enhancers leave a lubricant behind that protects the metal and continue to deoxidize the metal and improve the connection. They can work to lower the resistance and actually make a BETTER contact as time goes by. The best you can hope for from dielectric grease is that it seals it enough to not get much worse. I have used Caig Deoxit on my bikes for a few years now. I first found out about this on my job when I had to correct an issue in a scale load cell connector system that could not tolerate even 5 thousandths of an ohm of resistance drift. We had a connector in the field that had been improperly plated and was starting to drift, mostly in warm humid areas like Florida. Our testing showed that the Caig Deoxit could be a good long term fix. We ended up using the Deoxit to stabilize the bad units until we could get corrected wiring harnesses built with the correct connectors.  We also put a layer of Deoxit on the new parts to protect and keep them clean over their lifetime. This totally solved the resistance drift issue that we had. Our information on this product showed that the contact would actually get better for a period of over 1 year. The resistance would then begin to deteriorate, but at a much slower rate that a connector without the Deoxit. 

I still use a small amount of silicone grease on my spark plug caps. It helps to waterproof them and makes it easier to pull the cap off. (have you pulled a plug cap on a Stelvio yet?) But I use it in very small amounts and never near a relay or switch. 

Useful links:

1)      http://www.ia.omron.com/product/cautions/30/precautions_for_correct_use.html

2)      http://machinedesign.com/article/lubricating-electrical-switches-1025

3)      http://www.echeloninc.com/contactlubrication.htm

 

Wayne Orwig

 

Amen......... I use Motorcraft Electrical Grease on electrical connections. Silicone Dielectric compound on spark plugboots and heat-sink grease on parts that mount to a base with a heat-sink mount.

 People will probably not heed your message even though it is true.

Posted

Interesting articles Wayne,

I had no idea that silicone could form silicone carbide which we know is used in abrasives.

I worked for Volkswagen for a while, they wouldn't let silicone in the door, apparently they had trouble

getting paint to stick on parts made in a factory where silicone had been used on machinery.

 

I didn't see anything too negative about my Vaseline, I suspect it off gasses too to some extent

 

The Deoxit looks like a good product.

Posted

Silicone and paint do not mix...... Silicone and oxygen sensors do not go together. Most automobile service publications donot want silicone going through an engine because it will kill an oxygen sensor.

Posted

Could not find DeOxit by Caig locally. At the electronics supplier I found GC De-Ox-Id PArt # 19-1906-A. No silicone, but is it the same as Caig DeOxit?

Posted
Could not find DeOxit by Caig locally. At the electronics supplier I found GC De-Ox-Id PArt # 19-1906-A. No silicone, but is it the same as Caig DeOxit?

Fry's carry it if you have one near. It's magic in a can..

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