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Discussion Starter #1
Hey guys,

As a few of you might remember, this was originally basically a question about if gas was supposed to be coming from my petcock or not asked here: http://www.vn750.com/forum/showthread.php?t=11563

Well, because that thread doesn't have much to do with the real problem, my mysterious won't idle but runs great going down the road problem, I dove into the electrical parts of the bike today and here is what I found.

The problem in a pinch is that my bike runs perfect going down the road, idles great when cold/warm, but when I take it on a decently long trip, as soon as I come to a stop, it tries to die and I have to hold the throttle open to keep it idling.

I've put in iridium plugs, AGM battery, wires are good to the plugs, drained the carbs many times, reset the air/fuel screws on the carb to various lengths, finally settling upon about 3 turns out (this has helped with the popping from de-goating), relocated the R/R, drained the fuel tank and cleaned it out, cleaned the petcock screens, ran new vacuum lines/fuel lines, re capped all vacuum ports, still have this mysterious problem. It doesn't happen all the time, long trips and random. Other times it runs like a champ!


I started getting scared thinking it was the stator and/or R/R going out, so I wanted to look at the system. After diving into the electrical system of the bike today, I found the following.


Burnt and melted connectors/insulation from the stator connectors.



Yellow wires up top that they connect to, one of the connectors was almost off the wire:


This insulation tube that covers the stator wires was FULL of an oil/crap/water mix. I squeezed it from one end to the other and it just came out like a stream, I couldn't believe it. The entire wires and connectors were all coated in this water/oil mix crap. It was nasty. A LOT came out. I took it off completely and cleaned it out 100%.




The burnt/melted insulation I cut off:


the bare bullet connectors. I replaced these to be safe, they didn't look horrible, but not great either:

 

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Discussion Starter #2 (Edited)
I started by cleaning and sealing that insulation tube up with heat-shrink tubing at the top. This has made a good seal. Hopefully it will keep crap out of there better:



Bottom of stator wires heat-shrink sealed too:



Heat-shrinked the top connector yellow wires:



Stator wires crimped with new bullet connectors on clean wire:



Each one of the individual bullet connectors heat-shrink insulated to further protect them:



Same on top:



Finalized top connections:



Finished and connected:

 

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Discussion Starter #3
While I didn't get a chance to test my voltage before, I checked the stator before and after this, and before I was getting about 5 at idle, after wards about 18/20 ac volts. It seemed to climb rapidly with revs. Hopefully the stator and R/R are OK.


I didn't have a chance to ever test the volts directly at the battery when this idle problem was happening because it was very random, but I tested it out after I finished cleaning these connectors up.

Cold idle: 12v
Warm idle: 13v

When reved even a hair above idle it jumps quickly to 14v. So I'm hoping I'm good now and this was the source of my mysterious idling problem. **crosses fingers** What say you? Could it have been? My thinking was it pulling enough when riding, but not making enough because of the crap connection at idle with all the resistance of the nasty/dirty connections. I've hopefully solved my problem, won't know for a while one way or the other as it's rainy here and like I said the problem was very random.

I wish I had some better volt readings other than just 12, 13, and 14v, but unfortunately the volt meter I have is a very nice one, but it was given to me and is geared more towards AC than DC, the exact opposite of what I need/use one for, but it was gift and expensive so it's all I have for now.
 

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The Reanimater
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This is the way mine looked. Replaced wire/connections and (Knock on Wood) everything seems to be working fine.



 

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Discussion Starter #5
Ouch man! Mine look very similar!


I just want to be 100% sure, it doesn't matter which of the stator wires connects to which of the yellow wires as long as all 3 are connected right?
 

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The Reanimater
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Ouch man! Mine look very similar!


I just want to be 100% sure, it doesn't matter which of the stator wires connects to which of the yellow wires as long as all 3 are connected right?
Yes it DOESN't matter. Ennnie, Mennie, Minnie, Moe.........
 

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Discussion Starter #7 (Edited)
Great! Good to know. That's what I figured (and hoped since I randomly connected them and took it for a quick test drive round my block :D)





*EDIT*

I just noticed that the wires coming from your stator are yellow...mine are black.

What were the stock ones? Do you figure the previous owner had changed the stator already?


I was, in a way, hoping to get in there anyways. I think the gasket on the side cover on the bottom is shot and leaks a couple drips of oil every time I shut the bike off. I don't think I can stop this leak without taking the engine out to fully pull that side off and regasket it : /
 

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Looks like you did a great job ! But did you extend the wires so they are not close to that hot exhaust manifold ?
 

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Actually, those automotive-type bullet connectors are really poor for the type of current loads that can come from the stator. The quality of the crimp and the mating surfaces in the connector can degrade over time, and are aggravated when you start pulling multiple amps through it. Add to that the physical environment... vibration, dirt, moisture & heat you have connection that can quickly degrade.

Unless you replace them with a superior type connector (hard to find and expensive if you did) you really have to check on and replace these connections periodically. I plan to eliminate these connectors and solder mine directly then double heat-shrink the joints. That will last as long as the stator (or the engine itself).
 

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Discussion Starter #10
I actually WAS going to solder them, but I got to thinking that maybe it wouldn't be such a good idea in case the stator still had a problem. I plan to try it out for a could weeks, and if my issue is resolved, I will be redoing them and soldering them.


As for extending the wires, I didn't need to I don't think. I checked and I still had a decent amount of slack in the wire, but when I do go back to solder them, assuming this fixes my idle issue, I'll be extending them and routing them away from all sources of heat.



Actually, I HATE crimp connectors, I don't care what kind they are or what they're used for. I'm an audiophile and all my connections get soldered for everything. This was just a temp doing to ensure I didn't have to cut soldered wires apart in case my stator needs to be replaced anyways. Only time will tell if this solved my problem. It's hard to replicate.
 

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Search Goddess
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I'm going to throw out a word of caution here about the shrink wrapping all three stator wires..
See my album about my bike fire
http://www.flickr.com/photos/ddhughey0620/sets/72157600678734960/
We didn't shrink wrap the bundle, just wire-tied them together out of the way, but the heat generated from them was enough to "eventually" melt the wire insulation and cause a short which in turn caused an electrical fire. I had smoke rolling up from around the gas tank.. as I was riding

Those wires need a little bit of air circulating around them to cool them off.

A lot of folks have replaced the bullet connectors and just soldered the wires together. the bullet connectors are handy, but do seem to turn crispy after a while (probably from the same heat generated)
 

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This insulation tube that covers the stator wires was FULL of an oil/crap/water mix.
I checked my connectors and they look pretty good, no sign of burning or corosion. Just curious about water getting into the case.

I noticed that where the wires enter the engine case there doesn't seem to be anything to keep water out. Is this an area that should be sealed up?
 

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I'm going to throw out a word of caution here about the shrink wrapping all three stator wires..
See my album about my bike fire
http://www.flickr.com/photos/ddhughey0620/sets/72157600678734960/
We didn't shrink wrap the bundle, just wire-tied them together out of the way, but the heat generated from them was enough to "eventually" melt the wire insulation and cause a short which in turn caused an electrical fire.
Heat is not generated by the shrink wrap itself or wires being close together. Heat can only be generated by current flowing through resistance (ohms law: i.e. bad connections). If you shrink wrap a bunch of bad connections together, yes, the heat generated can eventually melt the insulation (shrink wrap) and arc over and potentially damage components and/or cause a fire.

Also, the "thickness" of the insulation must be adequate for the voltage between the two wires being insulated. The 30 or so volts that the stator puts out should not be any problem for good quality shrink wrap, but to be safe you can double shrink wrap. That will be more than sufficient to prevent arcing between wires.... that is unless the shrink wrap insulation is terribly defective (i.e. has holes in it)
 

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a couple of weeks ago I discovered the same problem. I posted this.
http://www.vn750.com/forum/showthread.php?t=11600
my wires were burned thru. After soldering in new sections of wire and shrink wrapping them i have had no other problems. I took a couple decent length trips and so far everything is ok. You should be good ro go.
 

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The Reanimater
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The problem I have with soldering the wires is, if the wires get hot enough to melt the insulation then it would be hot enough to melt the solder. Then the wires will come loose.
 

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Quote from Kontiki. ." Heat can only be generated by current flowing through resistance (ohms law: i.e. bad connections)". Therefore; eliminate the resistance and you have elimitated the heat source. Good low resistance connections or soldered joints do not cause heat. When resistance is eliminated the yellow wires will not get hot.
 

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The problem I have with soldering the wires is, if the wires get hot enough to melt the insulation then it would be hot enough to melt the solder. Then the wires will come loose.
While it is true if it gets hot it will melt plastic insulation ,the underlying reason the connections heat up is what Kontiki has pointed out ,a high resistance connection that will raise the temperature enough to melt the insulation. Soldering the clean and twisted together wires gives you a very low resistance connection and if you clean and twist the wires together before soldering you will have a mechanical as well as a solder joint,and I think the solder usually has a higher melting point than the plastic insulation
 

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The Reanimater
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I've worked in the Electronic repair biz. I'm telling you that if the wire gets hot enough to melt the insulation it will melt the solder joint.
I've fixed a lot of TVs by resoldering solder joints broken/cracked by heat from normal use.

When one end the wire gets hot it will travel the entire length of the wire and over any soldered spots.

What I like doing on a solder joint like these wires is to get a stand-off with a split down the side.
Solder up the wire then open the split on the stand-off so it will fit around the solder joint.
Then crimp it down so if the solder does heat enough to come loose the wires will still be crimped together and not come loose.
 

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Discussion Starter #20
I checked my connectors and they look pretty good, no sign of burning or corosion. Just curious about water getting into the case.

I noticed that where the wires enter the engine case there doesn't seem to be anything to keep water out. Is this an area that should be sealed up?
That's exactly why I sealed mine up. I couldn't believe how much water and oil mixture crap was in this tube, it was crazy. It took about 6 paper towels to mop it all up.


I would seal this up after making sure it's cleaned out and empty. It also probably wouldn't hurt to split the casing at the very bottom of the wire on both ends so it could drip out instead of staying sealed in there, but that also provides less protection for the wires. Difficult to say on that one.
 
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