Rectifier Question - YES I READ THE STATOR PAGES!

[bgk]

O.K. I honestly read the stator pages, a few times. I get the general idea, but I've got zero electrical diagnostics experience till now. I bought a cheap digital multi meter and I can set the meter to volts and put the probes on the battery posts and see if the system is charging and if it changes voltage with different RPM, lights on/off, etc. and I can set the meter to ohms and check for continuity from one place to another on the bike through wires, etc., but that's about the extent of my ability.

Here's the situation and question: I've got a 1979 GS1000L with separate regulator and rectifier units (the early GS bikes have separate units). Like most GS owners, I've suffered the classic poor charging system problems. I pulled my stator out and noticed a few coils were visibly fried and the ohm meter indicated shorting within the stator and/or wires. One of our GS Forum brethren Ray Snowden had a used (but very clean and undamaged) stator for sale on this site (assumed to be a stock Suzuki stator) off a 1982 GS1100 and I bought it, together with what I think is a aftermarket rectifier unit, which is labelled EMGO part number 48-98634. (A brief thanks to Ray. He is 77 years old, still loves and rides his GS, was a pleasure to deal with, and he carefully packed the parts for shipping as if they were crystal chandeliers!) The replacement stator is now in the bike, and the battery is charging nicely. However, the wires/connecters out of the stator in the area next to the air filter box are very hot. I'm guesing the classic Suzuki defective rectifier design as discussed in the stator pages. And I'm worried that I'll soon fry my new stator. The trouble is that the EMGO part I got came without any paperwork, diagram, etc. There are only four wires coming out of the EMGO unit rather than the five often discussed in the stator pages or elsewhere in the GS Forum for the combination regulator/rectifier units, and the ends of the wires are bare, no connecters to try and match up with stuff on my bike.

If I lay the EMGO unit on its back with fins facing towards me and wires at the top, from left to right, the first wire is yellow, the second is black, and the last two are yellow. Can anyone tell me what this unit is, what it does, which wires get connected where, what else I might need to buy, and anything else I need to finally solve my electrical problems ! Thanks in advance.

[argonsagas]

First thing, Brion, my experience has been that whether it is solid steel or electronic, when it comes to tools, you get the quality you pay for......

I have had no luck with cheap multimeters....

Re the regulator/rectifier...Hap Call is our resident epect, butI am curious about the wires mentioned.....the black one is expected to be gtround, and the three yellow ones are interchangeable as to their positioning, (but must NEVER be connected to each other, however there should be a red one as well, and I see no mention of it...

[argonsagas]

First thing, Brion, my experience has been that whether it is solid steel or electronic, when it comes to tools, you get the quality you pay for......

I have had no luck with cheap multimeters....

Re the regulator/rectifier...Hap Call is our resident expert, but I am curious about the wires mentioned.....the black one is expected to be gtround, and the three yellow ones are interchangeable as to their positioning, (but must NEVER be connected to each other, however there should be a red one as well, and I see no mention of it...

[bgk]

Argonsas, there definitely is not a red wire, nor any space or hole or broken fitting anywhere, where any other wire might have been. This is the big problem for me. I don't know what I've got, and I can't figure it out by trying to match up this unit with the wires on my bike or by reading through old posts on this website. It seems I've got the wrong number and/or color of wires compared to the stock Suzuki stuff or the aftermarket Electrex stuff. Thanks for your reply.

[bgk]

Argonsas, there definitely is not a red wire, nor any space or hole or broken fitting anywhere, where any other wire might have been. This is the big problem for me. I don't know what I've got, and I can't figure it out by trying to match up this unit with the wires on my bike or by reading through old posts on this website. It seems I've got the wrong number and/or color of wires compared to the stock Suzuki stuff or the aftermarket Electrex stuff. Thanks for your reply.

[SqDancerLynn1]

Don't know about your part I would suspect that the metal case is the ground, three yellow wires would go to the three yellow stator wires and the black wire that you have would go to the fuse box,thru the main fuse 15a and then to the battery. (Note one stator wire for the light circuit (w/r from the old rect) goes to the w/r of the harness thru the light switch to G/w wire to one of the stator wires) The other two stator wires go to the reg As to the hot wires it is best to eliminate the connectors and solder the wires together. Use crimp type connector but solder it instead of crimping, cover it with heat shrink tubing or electrical tape end results is that one stator wire should have one wire attached two of the stator wires should have two wires attached

[Anonymous]

Re: Rectifier Question - YES I READ THE STATOR PAGES!

However, the wires/connecters out of the stator in the area next to the air filter box are very hot.

From all I've gathered from my recent reading, and by way of my recent experience with charging system problems (fixed successfully), I would counsel you to see to those hot wires/connectors. The reason the wires/connectors are hot is almost certainly because you have poor connections there and increased resistance is causing the heat. In my case all that was necessary to solve my no-charge problem was to chop out those corroded connectors (and about 2 inches of hardened, heat damaged wire/insulator on each side) and to crimp, then solder, butt connectors in place. While you have the connections apart you can check the stator output as per the stator papers if you've not already done so: My Clymer manual and factory service manual both detailed exactly how to check the stator and regulator/rectifier. Remember to cut out any heat damaged wire because that will cause increased resistance by itself. Don't be fooled by the fact that your original connectors appear clean, or that you've cleaned them yourself - the original wire to connector crimp is not sufficient, and can't be properly cleaned. Good luck.

[bgk]

Thanks for your responses. I did a reasonably careful job checking wires and connecters, but did not know that the original factory wire to connector crimp was insufficient. I'll get to that aspect of the problem this weekend. Regarding SqDancerLynn1's response in particular, one thing I forgot to note in my first post is that the black wire out of the EMGO unit is a smaller gauge than the three yellow wires. It doesn't seem that all the juice in the system should travel through this skinny wire to the battery?

[SqDancerLynn1]

they could have used better wire but then the wiring harness on our would have been twice as big and it would have cost more to produce :roll:

[Hap Call]

My gut feeling is to agree with Ron on this one. You have to have three wires from the stator and these would be the three yellow wires. While most automotive and motorcycle systems use black as the ground or neutral wire, in this case the only remaining wire would have to be the hot wire so it would be the black one. The metal case is the ground here. Why the black wire is so small, I don't have a clue. I would normally expect it to be at least a 14-gauge wire, preferably a 12-gauge wire.

Another possibility is that the rectifier/regulator is for a bike with a two-phase stator. I believe Yamaha made some of these but I think they were mainly for enduro dirt bikes, which did not pull much current. I doubt this seriously because of the three yellow wires.

The safest way is to get an Electrex unit and put it on the bike. I know it cost some additional money but it is cheaper than replacing the stator and the R/R.

Hap

[bgk]

Thank you all for your reponses. As Hap Call has been called (accidental pun) the resident expert, and Hap Call doesn't know, then I guess I'm out of luck tring to figure this one out.

I'd love to go out and buy all new Electrex stuff. Trouble is I can't spend family budget money on my old GS without my wife going warpo! I keep the old GS alive by squireling away $20 here and $20 there, so the money stays "off her radar screen". Thats why I bought a used stator from a good GSer Ray Snowden on this web site, together with the mystery EMGO unit. I recently e-mailed Ray, and he e-mailed back that the unit came without paperwork from J.C. Whitney years ago. I'm going to inspect my wires, double-check my grounds, fix as necessary, and cross my fingers and hope that I don't burn out my replacement stator before I scrape up the dough to buy a new Electrex regulator/rectifier. Again, thanks for your input.

[argonsagas]

Brion:

Small point....as it appears your ground on the R/R is the case itself, be sure you clean the mounting bolt holes and the bolts very thoroughly so you get good contact, and it would not hurt if you added an extra stretch of wire from the mounting bolt directly to the negative post on your battery to ensure you have a very good ground.

I would take another step in the process, that being to mount the R/R securely, as above, then connect all the yellow wires, but NOT the black one. Have your multimeter handy, or even a test lamp, and connect the black wire from the R/R to positive post on your multimeter, or to either wire on your test lamp, and the other to the bike frame or negative post on the battery.

Before doing anything else, verify that all other wires to/from the battery and all connections to the stator are properly in place.

Then start the bike and immediately check the voltage reading from the black wire.


If you don't get any reading, or the lamp does not light, then the black lead is likely a negative wire and the R/R it is not for your bike and may cause damage if you continue.

Shut the ignition off and remove the R/R immediately, so no mistake is made in the future.


If it reads a good value of 14. or more, shut the engine down and finish your connections: it's a success.

BTW The Electrex R/Rs vary in price according to model, but they are all a LOT cheaper than Suzuki originals.... I don't recall the exact price, but I think mine was just over CA$200. two years ago. An extra point is that Electrex gives a two year guarantee....other folks just give you a receipt for purchase and say good-bye.