Burnt Stator Connector... (pic)

[bikedave99]

So I have my wiring all pulled out since I'm replacing my battery, and I notice the rectifier to stator plug looks a little gunky. So, I pull it apart to to clean it up.....:

As you can see obviously one of the connectors got extremely hot and melted the plug. You Can see it melted a hole around the male end of the plug. My question is, does this most likely indicate a burnt stator or a failed rectifier? I haven't yet put the ohm meter on it to check... Wonder if this is what killed my battery... Glad I found it before putting in the new one...

 

[mr.maxx]

hopefully it was just corrosion in the connector. ive seen that many times on other bikes.....the corrosion will create resistance and cause it to heat up and melt.

snip that outta there and hard wire it. i would.

 

[bikedave99]

hopefully it was just corrosion in the connector. ive seen that many times on other bikes.....the corrosion will create resistance and cause it to heat up and melt.

snip that outta there and hard wire it. i would.

I was kinda wondering if that was a possibility as well.... Good point! If the stator and recifier ohm out I think that is the route I'll take. I just thought I read recently that sometime when a stator section burns it can start cooking things. Thanks for the input!

 

[RaWarrior]

I'd just cut out the now ruined connector and directly splice the wires together (order doesn't matter it's AC). See if that helps your problem.

The stator-RR connector seems to be a fairly common point of failure for older bikes.

It's possible the stator could be going bad, wouldn't be the first..

check

->ground to each of the three stator wires...should be infinite ohms on all

->resistance between the three pairs of wires...should be in the .5-1.2 ohm range. 0 ohms or greater than ~2 indicates a burnt out or shorted winding.

-> AC voltage between the three pairs with the engine idling. I got around 20 VAC, that would steadily rise with engine RPM. All three legs should be very similar

While you're at it hardwire the R/R to the battery as well, and bypass the "crimp", lossy connectors, and inadequate wire gauge yamaha used.

 

[naughtyG]

I had a connector like that and it did fry my stator. Measure the voltage between the 3 wires (it's AC V not DC!) and if it goes above 60-70V when revving up it's most prolly fried - that's how mine looked.

 

[maleko89]

Rev bike up to 2500-3500 and it should be about 50 VAC.

 

[bikedave99]

Thanks for all the input gusy, I checked the resistance on the stator and all legs were .7-.8 ohms so it sounds like they are still ok? They are out of Yamaha spec but within Ra's range listed above. I also checked to make sure each leg is not shorted to ground and they all passed. I haven't had a chance to check the AC voltage yet since I haven't gotten the battery in yet. Before I crank it I will hardwire the connections as well as the rectifier to battery connection. I will also verify good ground on the rectifier. Will post back when I get it fired. Thanks again for all the responses!

 

[bikedave99]

Welp, got the new battery in and everything plugged back up and fire up the bike on just battery. Checked the AC at the stator plug and was getting 20volts at idle and about 40volts at 2000rpm on all legs so that looks good. I cut and hardwired the stator/rectifier connection but didn't have time to do the rectifier battery connection so I just plugged that back in to to do a quick test. I fired it up and got like 13.05 volts on the battery at idle.... hmmm... not the greatest. Rev it up and the voltage drops to mid to low 12s...

Cripes! Starting to suspect the rectifier now but will eliminate the remainder of the wiring first.

 

[naughtyG]

Hmmm, I think the voltage dropping on rev up points at a fried stator. Mine gave plenty of volts when testing, but didn't charge the battery at all.. Something to do with how it shows in neutral or under proper load. Hope yours is ok, although they're not that expensive and relatively easy to replace, bar the b****rds philips screw holding it in place!

 

[bikedave99]

Hmmm, I think the voltage dropping on rev up points at a fried stator. Mine gave plenty of volts when testing, but didn't charge the battery at all.. Something to do with how it shows in neutral or under proper load. Hope yours is ok, although they're not that expensive and relatively easy to replace, bar the b****rds philips screw holding it in place!

Interesting, I guess this could be a little like what Ra was dealing with on his bike. Proper output under no load, but once loaded and hot it fails... I just snagged a good deal ($14.95 shipped, woohoo!) on a newer mosfet rectifier so regardless I will be remedying that situation.

 

[Bill Seward]

Wire the output from your new R/R directly to the battery. In my case that improved charging by almost a volt!

 

[bikedave99]

Wire the output from your new R/R directly to the battery. In my case that improved charging by almost a volt!

I put a jumper in directly from the rectifier to the battery and fired it up to check the charging voltage and.... No better! The resistance in the existing circuit from the rectifier to the battery was .5 ohms so definitely more than it should be, but the by passing it with a jumper didn't help.

 

[wildweasel_pt]

Don't hardwire the RR straight to the battery, you need the 30amp fuse inbetween...

 

[88vmx12]

Hey guys, if any of you are having issues with fried connectors I have all of them instock with new terminals. Most are white in color

Thanks G

 

[bikedave99]

Alright, so I wired up my newer rectifier and had better charging voltage at idle (mid 13v) but when revved it would immediately drop into the low 12s. I had the ground on the rectifier hooked directly to the negative post. I noticed that the rectifier was getting quite hot which surprised me, so I decided to check my stator output voltage again. Each leg was consistently around 20v at idle but when revved up to 5-6k they all ramped up to over 80volts. They are all equal though, so it doesn't seem like anything is burned....80v too much? Anyway, I guess my next option is to strip all the wiring out in the charging circuit and replace it in case I have a break in the wireloom somewhere that shows fine continuity at low amperage but craps out under load. What a pain! Oh well... its only a matter of time before I find it. As an added aggravation, a PO of the bike stripped one of the allen head bolts holding the passenger footpeg on so now I have to easy out it to remove the old rectifier. The is even recessed so I can't get the vise grips on it. Hope I can drill straight...

 

[sdt354]

Rev bike up to 2500-3500 and it should be about 50 VAC.

+1, the best test going. All three legs tested 2 at a time.

 

[bikedave99]

+1, the best test going. All three legs tested 2 at a time.

I would say that is where all three legs came in at... I just wonder if climbing to 80volts is too much?

 

[wildweasel_pt]

I think you may have your stator gone fubar... The RR getting hot is evidence of that and 80 is a bit high. I tested my system due a bad RR and my stator was reading 50vac give or take throughout the RPMs range. I'd consider getting a replacement and try it on. Check with Sean and see if he can get you one for you to try and then if that is the culprit just wire him some money instead of the stator. I have a good one but im across the pond and shipping shouldn't be less than about 40 bucks...

 

[bikedave99]

I think you may have your stator gone fubar... The RR getting hot is evidence of that and 80 is a bit high. I tested my system due a bad RR and my stator was reading 50vac give or take throughout the RPMs range. I'd consider getting a replacement and try it on. Check with Sean and see if he can get you one for you to try and then if that is the culprit just wire him some money instead of the stator. I have a good one but im across the pond and shipping shouldn't be less than about 40 bucks...

I have come to the same conclusion... I have one ordered and it should be here this week hopefully. I need to get the required gaskets now too...

 

[88vmx12]

If you need the connector for the bikes harness I have them.

G