Nasty Hiccup

[dlaing]

I just cannot get my arms around the idea of using an insulating grease for the purpose of improving contact reliability. Battery terminal protection sprays and "goop" are to prevent corrosion from the outside. Useful on the outside of the connector to prevent moisture from getting in, but not on the terminals themselves. That defies common sense. Conductive paste to the mating contacts makes sense to me.

The outside of the connector is part of the terminal.

Battery teminal Insulating goop should not be used on the mating services, so no need to get your arms around that.

When the bolt is clamped down, embrace the idea of gooping it with battery terminal protectant. Works much better against corrosion than rubber caps that only prevent shorting from loose wrenches.

I used to use silicone dielectric grease and lube for bullet and spade connectors and it helps for a while, but I believe eventually the silicone becomes silicate and connection problems start, so now I just use it on the outside of bolt down terminals.

Spend the big money on a silver conductive paste and you will be much better off, but I use it very lightly where it might bridge connectors that should not be bridged. The ECU connector being a good example.

[Guest june]

Oh,it's not difficult.Check for vacuum leaks around the throttle bodies.

[Ryland3210]

The outside of the connector is part of the terminal.

Battery teminal Insulating goop should not be used on the mating services, so no need to get your arms around that.

When the bolt is clamped down, embrace the idea of gooping it with battery terminal protectant. Works much better against corrosion than rubber caps that only prevent shorting from loose wrenches.

I used to use silicone dielectric grease and lube for bullet and spade connectors and it helps for a while, but I believe eventually the silicone becomes silicate and connection problems start, so now I just use it on the outside of bolt down terminals.

Spend the big money on a silver conductive paste and you will be much better off, but I use it very lightly where it might bridge connectors that should not be bridged. The ECU connector being a good example.

 

Thanks for the clarification, Dave. We are on the same page, with a minor exception. While I have used corrosion protectant on the outside of battery terminals for car and boat batteries, it has not been my practice on motorcycle batteries. I haven't ever seen the kind of crude caused by battery acid which eventually seems to wick up the battery terminals on car batteries. Probably motorcycle batteries are better sealed. Of course, there is no harm to doing it on motorcycle batteries as well.

 

Even if the silicon grease never became silicate, it's still an insulator. Imagine if the connector's mating surfaces vibrate relative to each other. If that happens to any degree, the silicon grease can work its way between the mating contacts, reducing contact area and increasing contact resistance. Moreover, relative motion is undesirable, and grease facilitates that.

[Ryland3210]

Oh,it's not difficult.Check for vacuum leaks around the throttle bodies.

 

Read through all of the previous posts. I think you will appreciate that.

[dlaing]

Thanks for the clarification, Dave. We are on the same page, with a minor exception. While I have used corrosion protectant on the outside of battery terminals for car and boat batteries, it has not been my practice on motorcycle batteries. I haven't ever seen the kind of crude caused by battery acid which eventually seems to wick up the battery terminals on car batteries. Probably motorcycle batteries are better sealed. Of course, there is no harm to doing it on motorcycle batteries as well.

 

Even if the silicon grease never became silicate, it's still an insulator. Imagine if the connector's mating surfaces vibrate relative to each other. If that happens to any degree, the silicon grease can work its way between the mating contacts, reducing contact area and increasing contact resistance. Moreover, relative motion is undesirable, and grease facilitates that.

Yes, the connector's mating surface needs metal to metal contact.

A thin layer of dielectric compound increases resistance, but only very slightly, and it greatly reduces arcing and oxidation.

The silver conductive compounds are much better solutions at the mating surface because they reduce arcing, oxidation, AND resistance.

Silicone Dielectric Grease won't make bad connections better, it will only protect good connections.

Silver Conductive grease will make bad connections better, and protect them. The only drawbacks are the price and conduction where you don't won't conduction if you are sloppy, so use conductive grease sparingly if connections might bridge from oozing conductive grease. But realistically bridging would be difficult to occur on a motorcycles connections. Still the ECU connector is a place you would not to put a big blob of silver conductive paste.

Here is a pretty good write-up on Ox-Gard (a conductive protectant) compared with Silicone dielectric grease or lube.

http://www.olypen.com/craigh/oxgard.htm

One nice property of silver that I just learned of is that silver oxide is conductive unlike other metal oxides, so a silver conductive grease should theoretically last longer than say a copper conductive grease.

I really don't know if silicone compound breaks down into silicate, it is something that I have heard, but have been unsure of. It makes sense, IMHO.

[Ryland3210]

Yes, the connector's mating surface needs metal to metal contact.

A thin layer of dielectric compound increases resistance, but only very slightly, and it greatly reduces arcing and oxidation.

The silver conductive compounds are much better solutions at the mating surface because they reduce arcing, oxidation, AND resistance.

Silicone Dielectric Grease won't make bad connections better, it will only protect good connections.

Silver Conductive grease will make bad connections better, and protect them. The only drawbacks are the price and conduction where you don't won't conduction if you are sloppy, so use conductive grease sparingly if connections might bridge from oozing conductive grease. But realistically bridging would be difficult to occur on a motorcycles connections. Still the ECU connector is a place you would not to put a big blob of silver conductive paste.

Here is a pretty good write-up on Ox-Gard (a conductive protectant) compared with Silicone dielectric grease or lube.

http://www.olypen.com/craigh/oxgard.htm

One nice property of silver that I just learned of is that silver oxide is conductive unlike other metal oxides, so a silver conductive grease should theoretically last longer than say a copper conductive grease.

I really don't know if silicone compound breaks down into silicate, it is something that I have heard, but have been unsure of. It makes sense, IMHO.

 

I think your dissertation covers the issues, advantages/disadvantages quite thoroughly.

 

Whether silicon grease (it's different from "silicone") breaks down depends on what its compound is. I don't know what it's molecular structure is, but it is used in relatively high temperatures, such as spark plug boots, so it must be pretty stable. On the other hand, a 12 volts difference over a small distance is enough to cause chemical reactions with many compounds. Without the facts on this compound, however, you and I are just speculating on this issue. Personally, I don't feel any need to investigate in this case.

[dlaing]

Whether silicon grease (it's different from "silicone") breaks down depends on what its compound is. I don't know what it's molecular structure is, but it is used in relatively high temperatures, such as spark plug boots, so it must be pretty stable. On the other hand, a 12 volts difference over a small distance is enough to cause chemical reactions with many compounds. Without the facts on this compound, however, you and I are just speculating on this issue. Personally, I don't feel any need to investigate in this case.

I did not know there was a difference!.

So, I use Silicone Dielectric Grease which is made of silicon and oxygen and or silicon and carbon molecules.

Silicone is probably more stable than raw silicon.

But, yah, no need to investigate, just stay away from WD40, use silver conductive where safe to do so, and Silicone dielectric grease or spray where safe to do so when silver condutive won't do or is not available. For example the fuel injector terminals should be undone and mating surface and threads coated with silver conductive, and then bolted down and coated with silicone dielectric or maybe battery terminal coating such as http://www.webbikeworld.com/motorcycle-bat...rminal-cleaner/

I have never used the stuff, so I don't know if it is might cause over-insulation problems when re-clamped down, so I stick with silicone dielectric grease.

[dlaing]

So, what do you think of the Tyco relay?

[Ryland3210]

So, what do you think of the Tyco relay?

 

It turned out to have somewhat lower ratings than the GEI, as I recall. That's what motivated me to look into Omron to see if there was something better out there. I had a long term satisfactory track record purchasing their components, so I didn't look any farther into the Tyco's.

 

John

[Ryland3210]

I did some interesting testing just now, using a clip on ammeter as calibration back up to a storage oscilloscope. Here is what I found:

 

The starter solenoid draws a peak of 24 amps for between 20 and 45 milliseconds, and drops to 7.5 amps steady as the engine cranks. This peak is about half of what's implied by the coil resistance, so evidently the back emf caused by the motion of the solenoid keeps the current well below the theoretical 49 amps. The sudden reduction to 7.5 amps indicates that there is very likely a limit switch which cuts the current down to that holding current.

 

I saw no voltage spikes, so there is also likely to be some arc suppression installed.

 

Peak current might climb as high as 49 amps if the solenoid got stuck or was sticky for some reason. As I tested it several times, I noticed the time it spent at 24 amps decreased from the initial 45 ms down to 20. That is probably due to the increase of temperature with each trial.

 

This explains why there is only a 15 amp fuse protecting this ciruit. It will probably blow very quickly if the solenoid sticks for any reason. If battery voltage is low, the solenoid will take longer to pull in, which will cause it to spend more time in peak current mode, increasing the likelihood of blowing the fuse. It's a good idea to keep a spare fuse on hand. I keep several of different values in one of those little fuse boxes, under the rubber strap holding the tool kit down. I replaced the spare, which was rated at 15 amps, with a one-size-fits-all 30 amp'er, in case I get stuck somewhere. I can always replace that with the correct rating fuse later on when I get the chance.

 

Good news: Omron is trying harder to get me a sample of their heavy duty version. If that comes through, I'm confident it should provide long term relability, assuming it passes my vibration test. I'm waiting for docc's donated GEI to arrive to do that one last test.

More to follow.

[docc]

It went out today and should be in NY before the week is out.

[Ryland3210]

It went out today and should be in NY before the week is out.

 

Thanks, docc. It arrived yesterday, and I have some results to report.

 

I compared the construction of the GEI versus the Omron, and did a vibration test.

 

First of all, you will be happy to know that both of these relays passed the vibration test. I shook the heck out of them.

Neither relay showed any contact bounce over the frequency range for equivalent RPM's all the way up to 10,000.

The NC contact remained in contact throughout the test for both relays.

 

The construction comparison is as follows:

 

                                                      GEI  |  Omron

Moving contact material:   Silver alloy  |  Silver alloy

NC contact material:              Copper   |  Silver alloy

NO contact material:              Copper   | Silver alloy

Moving contact diameter: 0.085/0.083 | 0.099/0.098 inches

Terminal material:             Plated Brass | Plated Copper

 

The magnetic coils appeared almost identical. The Omron coil appeared to contain more copper. Both had flyback voltage suppression resistors.

The thermal conduction path for contact heat was better for the Omron, as it used heavier cross section conductors for the contacts through to the terminals, especially on the NO contact, which is used for starting.

 

In my opinion, there is no basis for the higher contact ratings claimed by GEI. If anything, they should be lower than Omron's ratings.

 

Omron has agreed to look into gearing up production again on an even higher rated relay for us, but I have to fill out some paperwork. I'm pretty satisfied with the current samples, but if they come up with a decent price for the 40 amp version, I would personally go for it, at least for the starter relay. More to come later. I hope to wrap this up within a week or so. It all depends on how fast Omron moves.

[docc]

Ryland, thanks!

[Skeeve]

Omron has agreed to look into gearing up production again on an even higher rated relay for us, but I have to fill out some paperwork. I'm pretty satisfied with the current samples, but if they come up with a decent price for the 40 amp version, I would personally go for it, at least for the starter relay. More to come later. I hope to wrap this up within a week or so. It all depends on how fast Omron moves.

 

Very cool info, thanks! Will the Omron be a plug-in replacement like the GEIs, or will some whittlin' need to be done on the relay socket to use the Omron for the starter relay?

 

Again, thanks for all the research!

[Ryland3210]

Very cool info, thanks! Will the Omron be a plug-in replacement like the GEIs, or will some whittlin' need to be done on the relay socket to use the Omron for the starter relay?

 

Again, thanks for all the research!

 

Hi Skeeve,

 

Thanks, it's a pleasure.

 

The Omron's are physically to the same specification as the GEI's. They plug right in. I have been running one in my bike for weeks now, with no problems.

 

Cheers,

John