TT, Don't know what kind of grease was used, but the grease itself (or through electrolysis) has attacked the terminals and what you're looking at is corrosion of the copper in the brass conductor. If you look carefully, you can see the untarnished grease in those areas on the connectors where there are no terminals.
The electrolysis comment is a very good point. A water film which bridges between a terminal that has voltage and a return to Batt Neg behaves as electrolyte, particularly if the water has impurities in in it. With such an occurrence, galvanic corrosion takes place, where ions from the anodic terminal and the cathodic contact points do an exchange, the results of which is a chemical conversion of the two dissimilar metals.
Referring to you posted picture, I can see what appears to be an ample amount of salts deposited on the mount plate. Also notice the solenoid terminals. The rusty one is where the battery positive cable attached and would have a charge potential whenever the battery held a charge potential. The plate is often attached to the battery negative. Or, many of the electrical contacts in the connectors provide returns to battery negative. Add electrolyte between two dissimilar metals with opposite electrical potential, and galvanic corrosion occurs. If the bike was operated with a wet film interconnecting all the electrically polarized components, corrosion is guaranteed.
In fact, this may be the best argument FOR putting dielectric grease on the terminals. I rather wish Honda HAD put it on there at the factory, as the electrical bits in the bike would be in MUCH better condition today.
I don't believe, and I can find no credible argument, to assume the grease has attacked the terminals. It was almost certainly put on there after the fact, and arrested further damage from corrosion. The grease then absorbed the copper oxide leached out of the brass plated terminals.
As I said, this isn't the only set of connectors that I've like this, and they have come from many different areas. So, the grease is either attacking the conductors because of the wrong grease being applied, too much being applied, or some kind of maintainance problem with the PO. Whatever happened, the excersize failed.
Wait a minute. Such conclusions are really conjecture aren't they?
If I go to a motorcycle junk yard and see 10 bikes with front end damage, is it reasonable to assume they were all caused by brake failure?
Clearly, the example you pictured shows an end failure condition. But, there is no evidence or science to support grease being the cause.
The "exercise failed" diagnosis includes the entire life experience of the pictured components with no time line marker as to when the grease was applied. How can a reasonable, substantive diagnosis be formulated under those conditions?
The corrosion chemistry and methodology have been well studied and are known. There is nothing in dielectric grease that promotes contact corrosion. In fact, it is the non-chemically active grease that provides a separation barrier, between the susceptible components, and the impurites of the the air and water which would otherwise come into contact with those metals.
It's been an interesting conversation. But, I am going to have to reject the notion that the picture provided demonstrates any negative effect of dielectric grease. It certainly shows evidence of neglect and or abuse, as well as a lack of understanding about what dielectric grease does and and how it should be used.
I'd say they applied grease to your terminals //after// there had been some major corrosion.
I concur.
Anyway my experience with it has been positive. Not using it (dielectric grease) is fine, Honda did on these bikes... and the connections lasted for decades.
Which was fine for Honda Marketing practices. No one ever expected (or wanted) them to last for 50 years. I maintain that many of the electrical issues dealt with in this forum, stem from corrosion of exposed metals in the electrical system that a dielectric grease could have prevented or at least delayed.
I'd say they applied grease to your terminals //after// there had been some major corrosion
Maybe in an effort to stop further corrosion, and it back-fired
There is no substantive evidence to support that conclusion. Neither is there a supportable argument from a chemistry science standpoint.
Not using it is fine, Honda did on these bikes... and the connections lasted for decades.
I don't think any of the major manufacturers grease their connectors, but that's just a guess. I know that Harley could easily have done this, but instead spent the time and effort to engineer O-ring connectors when connection problems arose.
I noticed on my 89 Camaro, that GM is using rubber sealed electrical connectors AND dielectric grease inside them, flooding the contacts.
Below, I've attached another electrical panel photo below (purchased on ebay with some other parts I needed, the Vreg was good!). I have no knowledge of its service history. But, it can't be newer than 1978.
Notice, it has no dielectric grease on the connectors, yet some of the terminals are showing some green and none of the terminals show the bright shiny brass color they did when new.
So from this picture:
What part of the terminal's condition is caused by the black over spray among the components?
Could the over sprayed paint have been the cause of the fuse terminal holder melting?
Could the over spray be the cause of the plastic connector crumbling?
Did the over spray cause the terminals to go dull and oxidized?
Is this a photo of the dangers of over spray?
Is this a photo showing the benefits of not using dielectric grease?
Can you find the nonsense in this post?
Cheers,