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Sat May 09, 2015 3:51 am

When points were the only thing some mfg attached a small felt strip that rode against cam, at oil changes a drop of oil kept it oiled, they started cheaping out as electronics arrived. I only do the finger wipe thing if needed some lube.

Sat May 09, 2015 5:52 am

Mallory and perhaps others used the felt strip. My personal opinion is that is a bad idea. Oil from the felt strip will creep along the points and contaminate the contacts. The arcing is quite intense from oil contamination and ignition energy drops significantly until the oil is burned off. The arcing also prematurely degrades the contacts. Oil needs to be used sparingly on the pivot and mechanical advance and shaft so that oil isn't flung up into the points, or the excess doesn't creep too far. Grease (and only a tiny bit to keep the lobes from corroding and to provide a tiny bit of lube) for the rubbing block and no oil there is best in my opinion. If you are using the points to trigger a CD box or other ignition a bit of oil on the points does no harm, but it sure does when having to switch the high current of the Kettering system. Fred

morymob wrote: When points were the only thing some mfg attached a small felt strip that rode against cam, at oil changes a drop of oil kept it oiled, they started cheaping out as electronics arrived. I only do the finger wipe thing if needed some lube.

Sat May 09, 2015 7:04 am

Vanapplebomb wrote: The dielectric grease isn't really a good lubricant. It is made to seal and protect electrical connections, and that is about it.

Silicone is an excellent lubricant. It's depends on the application, but it's true for all other lubricant categories.

In the present case we are trying to reduce friction between metal to plastic surfaces.

From Dowcornig website:

How silicone lubricants work
The purpose of lubrication is to:

Separate two moving surfaces with a softer and easier-to-shear liquid material or lubricant located between the surfaces.
Use pressure to increase the liquid’s viscosity, enabling it to separate the two moving surfaces and reduce the coefficient of friction or the force needed to move them against one another under an applied load.
Silicone oils, pastes, and greases contain long, linear polymers that slip easily over one another. This free movement gives them their lubricating properties.

Silicone pros and cons
Because of their low methyl-to-methyl intermolecular interactions and high backbone flexibility, silicone materials have:

A low glass transition temperature and remain liquid at room temperature, even at high molecular weight
High boiling points, and their viscosity is less affected by temperature changes than organics
However, the surface tension of silicone fluids is very low, and they tend to spread more than organics.

Their high spreading and high compressibility limit the internal pressures (viscosity increases) that can build within silicone materials when they are used as lubricants. This limits their load-carrying capacity compared to organic lubricants with the same initial viscosity. However, silicone lubricants do have sufficient load-carrying capacity for all metal-to-plastic and plastic-to-plastic lubrication applications.

From Permatex website

Sat May 09, 2015 7:13 am

Check out, Standard Lubricam SL-2. It is made by Standard Motor Products. It is according to the tube, for prolonging the life of points breaker arm rubbing block.

A local auto parts store that actually has some old time hot rod guys working there recommended and ordered it for me. Was about $5. Here is a link to the stuff on Amazon. The seller on Amazon happens to be the same auto parts chain I got it from. You may be able to find or order it at a local parts store that sells Standard products.

http://www.amazon.com/Standard-Motor-Products-SL2-Lubricam/dp/B000JKDAR6

Sat May 09, 2015 9:14 am

saw2 wrote: Check out, Standard Lubricam SL-2. It is made by Standard Motor Products. It is according to the tube, for prolonging the life of points breaker arm rubbing block.

A local auto parts store that actually has some old time hot rod guys working there recommended and ordered it for me. Was about $5. Here is a link to the stuff on Amazon. The seller on Amazon happens to be the same auto parts chain I got it from. You may be able to find or order it at a local parts store that sells Standard products.

http://www.amazon.com/Standard-Motor-Products-SL2-Lubricam/dp/B000JKDAR6

Thats good stuff and think it might be what I have, not lubriplate but lubricam? Tried to find it but things are disorganized :(

Sat May 09, 2015 9:54 am

PumaVW79 wrote: Vanapplebomb wrote: The dielectric grease isn't really a good lubricant. It is made to seal and protect electrical connections, and that is about it.

Silicone is an excellent lubricant. It's depends on the application, but it's true for all other lubricant categories.

In the present case we are trying to reduce friction between metal to plastic surfaces.

From Dowcornig website:

How silicone lubricants work
The purpose of lubrication is to:

Separate two moving surfaces with a softer and easier-to-shear liquid material or lubricant located between the surfaces.
Use pressure to increase the liquid’s viscosity, enabling it to separate the two moving surfaces and reduce the coefficient of friction or the force needed to move them against one another under an applied load.
Silicone oils, pastes, and greases contain long, linear polymers that slip easily over one another. This free movement gives them their lubricating properties.

Silicone pros and cons
Because of their low methyl-to-methyl intermolecular interactions and high backbone flexibility, silicone materials have:

A low glass transition temperature and remain liquid at room temperature, even at high molecular weight
High boiling points, and their viscosity is less affected by temperature changes than organics
However, the surface tension of silicone fluids is very low, and they tend to spread more than organics.

Their high spreading and high compressibility limit the internal pressures (viscosity increases) that can build within silicone materials when they are used as lubricants. This limits their load-carrying capacity compared to organic lubricants with the same initial viscosity. However, silicone lubricants do have sufficient load-carrying capacity for all metal-to-plastic and plastic-to-plastic lubrication applications.

From Permatex website

The lubrication that dielectric grease provides is not at all ideal for the cam/rubbing block. The lubricity of it functions more as an antisieze lubricant than anything else. It is quite poor when it comes to high speed shearing between two loaded points. There are much better lubes out there such as your ordinary joe-blow synthetic wheel bearing grease which is made for loaded high speed shearing. Just because dielectric grease is touted as being a good lubricant does not mean it provides the correct kind of lubrication for every job. In the case of the cam/rubbing blocks, it does not.

Sat May 09, 2015 10:10 am

Vanapplebomb wrote: Just because dielectric grease is touted as being a good lubricant does not mean it provides the correct kind of lubrication for every job. In the case of the cam/rubbing blocks, it does not.

Why not? Are you saying silicone grease is not a good lubricant for thermoplastic polymers?

Sat May 09, 2015 10:53 am

PumaVW79 wrote: Vanapplebomb wrote: Just because dielectric grease is touted as being a good lubricant does not mean it provides the correct kind of lubrication for every job. In the case of the cam/rubbing blocks, it does not.

Why not? Are you saying silicone grease is not a good lubricant for thermoplastic polymers?

Not at all. There are many great silicone greases out there that work well for many different applications. But, not all silicone greases are created equal. Dielectric grease is made to keep connectors etc from seizing over time and be a light assembly lubricant to make plastic electrical connectors easier to plug in and unplug, to not break down under high voltage, and provide a seal to keep contacts from corroding due to exposure to the elements. Thats about it. So yes, dielectric grease is great for lubricating polymer slip fittings, etc, but it is not a good lubricant for things like cam/rubbing blocks, bearings, etc. Dielectric grease doesnt have an additive packages with good friction modifiers and anti wear stuff. Grease in and of itself is pretty poor as far as lubrication goes. What makes or breaks a grease for wearing parts is the additive package. Dielectric grease doesn't have that, period. It is what it is.

Sun May 10, 2015 6:23 am

Vanapplebomb wrote:
Not at all. There are many great silicone greases out there that work well for many different applications. But, not all silicone greases are created equal. Dielectric grease is made to keep connectors etc from seizing over time and be a light assembly lubricant to make plastic electrical connectors easier to plug in and unplug, to not break down under high voltage, and provide a seal to keep contacts from corroding due to exposure to the elements. Thats about it. So yes, dielectric grease is great for lubricating polymer slip fittings, etc, but it is not a good lubricant for things like cam/rubbing blocks, bearings, etc. Dielectric grease doesnt have an additive packages with good friction modifiers and anti wear stuff. Grease in and of itself is pretty poor as far as lubrication goes. What makes or breaks a grease for wearing parts is the additive package. Dielectric grease doesn't have that, period. It is what it is.

Silicone Dielectric Grease is still a low viscosity grease, just better at holding off high voltages -- it is a wrong assumption that it should be used only on electricity.

As stated by the technical data sheet of the manufacturer, it is an "excellent lubricant on rubber plastic and ceramic". And according one of the most important industries "silicone lubricants do have sufficient load-carrying capacity for all metal-to-plastic and plastic-to-plastic lubrication applications."

So, what we have? A metal-to-plastic interface and a silicone lubricant. What more do you want? A better package? Go ahead there are some, it's good for the economy etc. -- but that one is just right.

It's far from a poor choice, in fact is the better choice I have in my toolbox for this application -- and I do have a fair amount of lubricants. I won't be surprised if I discover that the formula of the venerable Bosch distributor grease is nothing more than silicone grease with some "additives". I've been using the Permatex tune-up grease on the distributor shaft for some years without complaints. It just works.

The video below was shot yesterday. Last time I lubricated the shaft is more than 1000 miles ago.
It is a really simple test and easily repeatable: If the shaft were "dry" it means I have been using a "pretty poor" lubricant. Let's see:

Sun May 10, 2015 8:34 am

I never said use only on electrical connections, just that it is not ideal for lubricating the cam/rubbing block. It's like using butter as an amble paste for an engine. Sure, it will work, but there are a lot better options out there.

**Edit**

Heck, even a very small amount of synthetic high temp disk brake wheel bearing grease would work better for the cam/rubbing block, and who doesn't have a tub of that sitting around the shop for emergency use? For others reading, don't use to much, because even high temp disk break wheel bearing grease can get flung around, especially if you use to much. You can use what you want, but I think you ned to do some more research on material properties and do less reading of product sales brochures for technical information. :wink:

Sun May 10, 2015 8:53 am

Wow to think I've been using hi temp wheel bearing grease for the point lube on my VW's and hundreds and hundreds of others for thousands and thousands of miles with no problems. And as long as you have your car with you with you, it is readily available ~ altho not in a convenient tube :lol:

Sun May 10, 2015 9:03 am

Yup, I have used that too in a pinch. Worked alright, but a bit messy, even when using the grease sparingly. After a while I just got new points that came with a small capsule of grease, wiped the grease of the cam, and used half the capsule on the cam. Then I saved the other half and stuck it with the points on a shelf until someone else needed a set. The distributor grease sticks to the cam super well. Buddy of mine just changed his points after 22,000 miles because the tungsten point contractors were shot. He used the distributor grease that comes in the capsule when the points were replaced and the rubbing block surprisingly still had some life left in it after all those miles...though not much. I have seen the same points with other greases have the rubbing block wiped out in half the distance.

Sorry about editing the above post while you were posting. :lol:

Sun May 10, 2015 9:23 am

Puma, I also wouldn't use dielectric grease. It might be good enough, but I doubt it is made for high speed lubrication. Also, the finger test you used really doesn't prove anything except that the lube didn't rub off where the rubbing block never sits. The flat spots on the cam lobe never come in contact with the rubbing block. I'm not saying that the dielectric grease won't suffice, I'm just saying there is probably something better like the Bosch stuff. I just use a tiny bit of wheel bearing grease which I'm sure isn't the very best choice either. Good thing the lubrication demands are low since almost anything will do. Except oil! Fred

PumaVW79 wrote: Vanapplebomb wrote:
Not at all. There are many great silicone greases out there that work well for many different applications. But, not all silicone greases are created equal. Dielectric grease is made to keep connectors etc from seizing over time and be a light assembly lubricant to make plastic electrical connectors easier to plug in and unplug, to not break down under high voltage, and provide a seal to keep contacts from corroding due to exposure to the elements. Thats about it. So yes, dielectric grease is great for lubricating polymer slip fittings, etc, but it is not a good lubricant for things like cam/rubbing blocks, bearings, etc. Dielectric grease doesnt have an additive packages with good friction modifiers and anti wear stuff. Grease in and of itself is pretty poor as far as lubrication goes. What makes or breaks a grease for wearing parts is the additive package. Dielectric grease doesn't have that, period. It is what it is.

Silicone Dielectric Grease is still a low viscosity grease, just better at holding off high voltages -- it is a wrong assumption that it should be used only on electricity.

As stated by the technical data sheet of the manufacturer, it is an "excellent lubricant on rubber plastic and ceramic". And according one of the most important industries "silicone lubricants do have sufficient load-carrying capacity for all metal-to-plastic and plastic-to-plastic lubrication applications."

So, what we have? A metal-to-plastic interface and a silicone lubricant. What more do you want? A better package? Go ahead there are some, it's good for the economy etc. -- but that one is just right.

It's far from a poor choice, in fact is the better choice I have in my toolbox for this application -- and I do have a fair amount of lubricants. I won't be surprised if I discover that the formula of the venerable Bosch distributor grease is nothing more than silicone grease with some "additives". I've been using the Permatex tune-up grease on the distributor shaft for some years without complaints. It just works.

The video below was shot yesterday. Last time I lubricated the shaft is more than 1000 miles ago.
It is a really simple test and easily repeatable: If the shaft were "dry" it means I have been using a "pretty poor" lubricant. Let's see:

Sun May 10, 2015 9:59 am

Glenn wrote: Spend the $10 and get the Bosch grease.

Glenn
What vendor sells the Bosch grease for $10?

Sun May 10, 2015 1:03 pm

Fred Winterburn wrote: Puma, I also wouldn't use dielectric grease. It might be good enough, but I doubt it is made for high speed lubrication. Also, the finger test you used really doesn't prove anything except that the lube didn't rub off where the rubbing block never sits. The flat spots on the cam lobe never come in contact with the rubbing block. I'm not saying that the dielectric grease won't suffice, I'm just saying there is probably something better like the Bosch stuff. I just use a tiny bit of wheel bearing grease which I'm sure isn't the very best choice either. Good thing the lubrication demands are low since almost anything will do. Except oil!

The grease don't "know" if something is spinning or not. The only things it "knows" is if it's molecules are not breaking down and consequently able to slip easily one over another.

As you can see in the video, I have touched the top of the cam lobe -- not the flat surface.

If the wheel bearing is petroleum derived, it is not compatible with plastics therefore not ideal.

Sun May 10, 2015 2:22 pm

Puma, I will accept your word that the grease came off the lobe and not the flat of the cam. By the way, there are plenty of applications where plastics and metals are lubricated together with petroleum based greases. Dielectric grease was formulated for a different purpose other than high speed sliding contact, but may very well be acceptable despite that.
We could probably even go back to the beginning of the last century and use some animal fat derived greases on this application without any problems too. Fred

PumaVW79 wrote: Fred Winterburn wrote: Puma, I also wouldn't use dielectric grease. It might be good enough, but I doubt it is made for high speed lubrication. Also, the finger test you used really doesn't prove anything except that the lube didn't rub off where the rubbing block never sits. The flat spots on the cam lobe never come in contact with the rubbing block. I'm not saying that the dielectric grease won't suffice, I'm just saying there is probably something better like the Bosch stuff. I just use a tiny bit of wheel bearing grease which I'm sure isn't the very best choice either. Good thing the lubrication demands are low since almost anything will do. Except oil!

The grease don't "know" if something is spinning or not. The only things it "knows" is if it's molecules are not breaking down and consequently able to slip easily one over another.

As you can see in the video, I have touched the top of the cam lobe -- not the flat surface.

If the wheel bearing is petroleum derived, it is not compatible with plastics therefore not ideal.

Sun May 10, 2015 3:38 pm

Fred Winterburn wrote: Puma, I will accept your word that the grease came off the lobe and not the flat of the cam. By the way, there are plenty of applications where plastics and metals are lubricated together with petroleum based greases. Dielectric grease was formulated for a different purpose other than high speed sliding contact, but may very well be acceptable despite that.
We could probably even go back to the beginning of the last century and use some animal fat derived greases on this application without any problems too. Fred

Fred, almost sure that simple test was well conducted, but I will double check on another occasion and will post the results here. As I've said before, it's an easily repeatable test, if someone want to try and come to a different results he/she is welcome to post the conclusions here.

Sun May 10, 2015 5:37 pm

I'm gonna back up Fred. Phenolics or Nylon polymers, which most rubbing blocks are made of, are not negatively impacted by petroleum based greases, or synthetic blends, or fully synthetic based greases.

Puma, I'm still not sure how your test actually proves it is a good lubricant for the purpose. The only thing I see it proving is that after a few thousand miles, there is still dielectric grease on the cam. Just because it is there doesn't mean that the grease is providing adequate lubrication and wear resistance characteristics. That is something you can only tell in a study with many many samples over many many miles OR in a controlled study rotating the shaft/cam a standardized number of times and measuring the amount of wear on the blocks used with different lubricants as Bosch would have done. If you and a few dozen others using dielectric grease can make a rubbing block last 20,000 miles like a dedicated distributor grease, then I might be persuaded to reconsider my statement. I have serious doubts due to the lack of practically any anti wear and friction modifiers in dielectric grease. Sorry to say it, but until then, claims would just be speculation and vapor. :wink: