81 GS 550 - Bad stator - possibly bad PO rectifier wiring(?)

[Guest]

Hello all,

I think I've diagnosed the issue so this is mostly just a sanity check. Please let me know if this diagnosis seems accurate (Thanks!)

I ran into a problem recently with the battery getting weaker after a few days; eventually dying while coming to a stop w/ the headlight on for the first time (only got a few blocks on our first night ride yay!)

Read through a lot of different charging threads in addition to the requisite Stator pages in their many forms. I did all the quick charge tests (voltage never increased w/ rpm change, just stuck around the same 12.65v as "on but not cranking" and idle) which showed me it wasn't receiving any charge... performed leg-to-leg stator resistance (showed ok. i believe .8ohm all around) and leg to ground resistance check (auto-ranging DMM shows OL, but manual range DMM originally showed some resistance so was leaning towards stator)...Finally it looks like I've got a bad stator after finding only 2-3VAC coming off each stator leg while running up to 5krpms(possibly melted to the cover?)

So it seems I need a new stator. Was either gonna order off of Rick's Motorsport Electrics (they have the stator cover gasket in stock too) or Electrosport as recommended by BassCliff's site unless there's another source GS'ers recommend for a solid replacement.


BUT WHAT ABOUT THAT RECTIFIER??
I'm not sure that this 81 GS 550 has its rectifier connected correctly! Really don't want to buy a new stator if there's other electrical gremlins waiting for it from the PO!!!

Its a 5-wire R/R unit.
(3) yellow wires direct to the stator (yellow wires on both sides so possibly already a replacement stator?)
(1) black wire direct to battery Neg(-) terminal
(1) red wire direct to starter solenoid post/nut which also has the large gauge red wire going to the battery Pos(+) terminal

Its that red R/R Pos(+) output wire that has me questioning so much. From what I've ready on other threads this wire should be going direct to the battery Pos(+) terminal with an inline fuse OR into the factory loom and through the factory 15A fuse which would then exit the fusebox to the starter solenoid and battery Pos(+) (or is it direct to battery from fusebox and then the solenoid joins at the battery POS(+) terminal?). Either way it seems like it should pass through a fuse to safeguard against current but doesn't seem to be making use of the fuse at all.

Any and all help is appreciated. I'll try to get some photos of the wiring up tomorrow when there's some light.

Thanks GS Fam!

[tom203]

Resistance checks on stators are iffy..

Do this test.. Disconnect stator leads from r/r. with your multimeter set on 200vac scale (or same scale that you would use for house outlet) While running bike to about 4k to 5k rpms, measure stator lead to stator lead and note the 3 readings. At same time and same meter scale, put one meter probe on any stator lead and other probe on good bike ground - you want to see a very low voltage reading, 0 would be best.

original factory setup had red wire from r/r going into harness after the main 15 amp fuse- here's a link
http://www.thegsresources.com/_forum/showthread.php?152769-GS-Charging-System-Health&p=1138898#post1138898

make sure you read about series r/r's like the SH-775...

[Steve]

You likely need a new stator AND a new R/R, but you definitely need to change the positive wire attachment point. Currently (pardon the pun), it is attached to the battery post on the solenoid. Electrically, that is the same as if it were connected directly to the battery. (I prefer to attach wires to the solenoid to minimize the number of wires at the battery posts.) Unless there have been other changes to the wiring (likely not), you should have that R/R output wire connected to the stock wire, which joins the harness between the MAIN fuse and the ignition switch.

There are several opinions about which stator is best, so I will let others chime in on that, but the overwhelming favorite R/R is the Shindengen SH775, which is typically found on newer (since 2011 or so) Polaris RAZR vehicles. New ones have skyrocketed in price, but there are PLENTY of used ones available on eBay for about $40, but you have to look at them carefully to make sure you get the genuine article.

.

[SunsetTwist]

Bit the bullet and ordered the new stator from Rick's. Didn't look at ebay until afterwards...definitely much cheaper on there but i'm telling myself I made the "quality" purchase right now.

In regards to the R/R I'm looking up more info about the SH775 right now but for the time being wanted to clarify a few things about the current (more punniness) wiring.

I followed the Pos(+) output wire from the R/R that currently leads to the starter solenoid, to another red wire leading into to the 15A fuse (installed in the main fuse box) and found the other end of the fuse connects to a red wire w/ a bullet connector which quickly disappears into the wrapped factory harness.

Question: Is that red wire w/ the bullet connector where I should be making the "T connection" for the R/R output? It seems like this should be the wire coming from the ignition switch since it leads into the main 15A fuse but I can't seem to find the connection which would have been used by the factory R/R. Does this mean I need to splice and solder? Totally fine if that's what needs to happen I just wanted to double check before tearing into it.

[tom203]

Some PO altered the stock layout, probably buried the t-connection that Steve was refering to.

not sure why this didn't show up, but let's repeat

http://www.thegsresources.com/_forum/showthread.php?152769-GS-Charging-System-Health&p=1138898#post1138898

[SunsetTwist]

Much more research of old threads has brought me to this point. Please correct me where I stray from the intended wisdom gained from TheGSResources.

DISCLAIMER:: THIS WIRING IS BELIEVED TO BE INCORRECT. PLEASE REFERENCE IT ONLY AS A CAUTIONARY TALE AND NOT TO WIRE YOUR CHARGING SYSTEM.


This is what the wiring between the battery, R/R, fusebox, and starter solenoid look like at the moment. In the first photo the small black/white wire is coming from the R/R NEG(-) output where it joins what I believe is the engine ground strap(its a wire bolted to the engine not the frame) at the Battery NEG(-). The only wire connected to the Battery POS(+) goes to the stack of four wires connected at the starter solenoid in the next photo. (See next photo)






This photo shows the R/R POS(+) output wire connected to the starter solenoid. Beneath it is a red wire going to the white fuse box which I've read is an optional connection for accessories, but currently is a dead end. Directly above the R/R output on the same post is the combination of the red harness wire coming from fusebox 15A main circuit, as well as the large gauge wire which goes to the Battery POS(+). The yellow/green wire going to harness looks like the starter solenoid NEG(-) return.



From everything I've read this is incorrect. R/R output should be routed into either the old harness before the fusebox, or should be connected direct to Battery POS(+) w/ an inline 20A fuse. Either way it should have a fuse between it and the battery. R/R negative should be connected to a Single Point Ground separate from the Battery NEG(-), preferably on one of the R/R mounting bolts, to reduce distance, where it should also be joined by a frame ground wire, and Battery NEG(-) wire. (PLEASE LET ME KNOW IF I"M GETTING THIS PART CORRECT). Also am I crazy or is there no harness NEG(-) included in any of these connections to the R/R or battery?? Currently the R/R NEG(-) is only seeing the Battery NEG(-) and the Engine Ground. In every one of the following photos courtesy of PosPlayr there is a harness return wire grounded to either the SPG or to one of the R/R mount bolts. Sorry if this seems like a long or an ignorant question but what am I missing here?


I've been staring at this diagram and many more from PosPlayr which have helped me get this far.





It seems like the PO may have changed out the R/R and stator previously but wired it incorrectly. Trying to only learn from these mistakes, not repeat them.

Again, many thanks for any/all replies or even just for dropping in to share some knowledge on your own journey.

[cowboyup3371]

You might want to move your pictures to Imgur or Flickr as we cannot see them thanks to Photobucket's user unfriendliness

[SunsetTwist]

Thanks for letting me know cowboyup3371

I switched these over to imgur so hopefully they stay functional a bit longer