Use of Dielectric Grease

[Colin24]

I am in the middle of reassembling the FJR to get it ready for the forthcoming riding season. I had the bike stripped down to the valves so I could check the valve lash. (No adjustment needed, woohoo!)

I had to disconnect many of the electrical connections in the process. For the most part I am impressed with the connectors used on the bike. The seem to seal well and positive lock and keep the weather out.

But there were a few connectors that showed signs of moisture getting in and starting to cause some corrosion of the connectors. I cleaned them up as best as I could with electrical contact cleaner and they should be okay.

Now, I am treating this bike like I intend to own it for many years and many miles to come. So I have been making sure I put in the extra little effort during any maintenance cycle.

So I have decided to use dielectric grease on all the electrical connections that I am working with during this down time. Is this a good idea? In short which of the following would apply:

A - This is massive overkill but still a good thing to ensure years of trouble free service.

B - This is overkill and it really isn't worth the effort. But it wont cause any harm.

C - Probably shouldn't do it but it probably wont cause any problems.

D - Dont do it, it will ruin your bike.

I am thinking the answer is A. But I am curious to know what the collective wisdom of the group here thinks

- Colin

 

[Rogue]

I think B, but if you have it you might as well use it.

 

[radman]

I use dielectric on every connector I touch whenever it will not cause a problem with it in some other way ( such as the possibility of silicone contamination of the O2 sensor for instance). You are doing the smart thing, weatherpack seals are not foolproof, nor are they always waterproof. Protection of low voltage circuits, critical to the smooth operation of a sophisticated feedback controlled fuel injection system is about as smart a thing as you can do, your forsight is to be commended.

 

[Bounce]

A

You're already there. And that whole "ounce of prevention" cliche has real merit in these cases.

 

[Warchild]

A.

 

[Fallen Jim Rides again]

Well, you have already heard from the guys who count most but consider this.

Yamaha knows perfectly well that the overwhelming majority of bikes sold will likely never see 50000 miles. Most will never be ridden much in inclimate conditions. It is not cost effective to build them as if they were. Simple arithmetic. That said, the fact that we can purchase effectively a 5 year unlimited milage warranty suggests that they have some faith in the engine and power train so the bike CAN be ridden much farther than most do.

Also, my personal experience has been that the most common minor problem is with the electrical system and very often it is exactly the connectors where the problem lies.

My vote - none of the above.

Like Rad, I think this is a very good idea, if you plan (as do I) to ride the bike for a very long time and many many miles.

 

[charismaticmegafauna]

Fallen Jim Rides again Posted on Mar 2 2006, 10:23 AM<snip>

It is not cost effective to build them as if they were. Simple arithmetic. That said, the fact that we can purchase effectively a 5 year unlimited milage warranty suggests that they have some faith in the engine and power train....

Not much disagreement with the bulk of the post; but, I think making an inference about Mama Yama's product faith from the warranty might be a stretch? I think the warranty is purely a numbers thing, a business decision, a financial money-maker (insurance, actuaries, etc.) -- anything that might happen is paid-for-in-advance by the deposits (and interest) from the monies collected beforehand. jmho

apologize, too, if this becomes thread 'jacking?

 

[Fallen Jim Rides again]

I think we're on the same page cmf. That is why I said SOME faith. Posts about Yamis getting over 100000 miles bear it out. I think. YMMV

You guys who have more experience with adding electrical stuff; What do you think about crimp, dielectric grease, heat shrink for our custom connectors?

 

[jestal]

I would add a vote for "A" with one small caveat. Do not grease up the O2 sensor.

There is another concern with the hermetically sealed connectors that hasn't been mentioned. The connectors are sealed SO good that virtually nothing ever gets into them...but...if the seal is broken some how and moisture does get in it can really wreak havoc since it likely cannot get back out again. I have seen cases (not just one...LOL) where "moisture" entered a sealed wiring harness at an open connector and then migrated thru the wiring harness until it got into the controller/ECM and then destroyed the controller. An example might be like disconnecting an 02 sensor and leaving the blank connector open and hanging in the elements. A previously sealed connector can now wick moisture into the exposed wire and then the moisture will wick along the wire until it enters the end of the circuit at the ECM. This came to light many times when vehicles started running strangely and the ECM was suspected. Upon removing it you could shake the hermetically sealed PCM and hear water inside!! The water wicked along the wires from an open connector and collected inside the PCM.

Granted, this isn't the most common or likely failure mode but it can and does happen. Sealing a connector with the dielectric grease is a good idea and it can block the transfer of moisture along a wire if it tried to traverse a sealed connector from another source.

The wicking action of moisture along the wires is very strong and if you have ever stripped a trailer lightly harness and found green wire several feet from any connector you understand that the effects of corrosion are not limited to the bare ends of the wire.

Most O2 sensors actually receive the "air" for the oxygen reference signal on the back side of the element inside the O2 sensor from air wicked along the wires connecting it to the ECM or controller. Older O2 sensors had the air reference from the shell itself but the O2 sensor can be a source of moisture inside a harness as the signal conductor to the O2 is sealed back to the ECM and is open on the end to the elements if the whole O2 sensor is not sealed. Sealing the O2 prevented the O2 from getting an oxygen reference but engineers learned long ago that the wire harness itself would carry plenty of air to the sensor just thru the small spaces between the wire strands. Point of all this is that you do NOT want to dielectric grease the connectors to the O2 sensor if you want it to keep working....LOL. It needs to wick air to the sensor.

 

[mech 1 twa]

Honda AUTOs had a few recalls with corrision at fuel pump connertor. They were assembled with moisture in connectors. Sealed so good it couldn't dry out. Caused all kinds of problems, no start, fuel gauge inop.

Many had to have fuel pump and harness pins replaced.

 

[C&C]

I would modify "A" to read, A - This takes little time to do and will help ensure years of trouble free service.

 

[yamaholic]

A

For the long haul--an ounce of prevention is worth a pound of cure...