Author Topic: quick charging test (Read 9436 times)

Rusnak_322 · « **on:** October 04, 2016, 01:28:07 PM »

My bike is not charging. when running it is showing 12.2 volts - about the same as right before I started it.

What is a quick way to test that the stator is working? There is a red and two yellow wires coming out.

I want to determine if it is my wiring or the stator is bad.

1975 850T

thanks,

Wayne Orwig · « **Reply #1 on:** October 04, 2016, 01:34:47 PM »

You are talking about a Bosh system, right?

Does the dash light work?

The current through the bulb provides the startup current.

Rusnak_322 · « **Reply #2 on:** October 04, 2016, 02:50:22 PM »

aftermarket speedo, no tach.
it is a stripped café bike that I bought with a horrible wiring harness. lots of those cheap auto part store male/female spade connectors. Sometimes a connector splice 6" or 8" from another one for no reason other then I guess to not have to use 1 longer wire. But it ran when I got it and I assume that it charged, as it started and ran after a few rides.

here is the diagram that I made up when I took it apart. I know it is a mess - it wasn't made for any other reason other then help me get it back together easier. the 1-12 on the left side is the speedo connectors. As of right now, it runs and starts as long as the battery is charged.

Chuck in Indiana · « **Reply #3 on:** October 04, 2016, 03:24:03 PM »

Quote from: Rusnak_322 on October 04, 2016, 01:28:07 PM

My bike is not charging. when running it is showing 12.2 volts - about the same as right before I started it.

What is a quick way to test that the stator is working? There is a red and two yellow wires coming out.

I want to determine if it is my wiring or the stator is bad.

1975 850T

thanks,

Check ac voltage on the two yellow wires. If the alternator is working, it'll be 45 volts or so. If so, the problem is more than likely the regulator. Put a couple of paper match sticks or equivalent between the brushes and slip rings. Check ohms on the slip rings. Should be around 3 from memory, always a dangerous assumption.

Naturally, open or shorted means bad rotor, the normal failure of the Bosch system.

Wayne Orwig · « **Reply #4 on:** October 04, 2016, 03:31:55 PM »

Quote from: Rusnak_322 on October 04, 2016, 02:50:22 PM

aftermarket speedo, no tach.
it is a stripped café bike that I bought with a horrible wiring harness. lots of those cheap auto part store male/female spade connectors. Sometimes a connector splice 6" or 8" from another one for no reason other then I guess to not have to use 1 longer wire. But it ran when I got it and I assume that it charged, as it started and ran after a few rides.

here is the diagram that I made up when I took it apart. I know it is a mess - it wasn't made for any other reason other then help me get it back together easier. the 1-12 on the left side is the speedo connectors. As of right now, it runs and starts as long as the battery is charged.

Still need to know what charging system is in it. Bosch, Ducati? The photo doesn't help much.
Or at least pull the cover from the stator/rotor and get a photo.
Does it have a regulator/rectifier with a heat sink?

Two Checks · « **Reply #5 on:** October 04, 2016, 03:33:40 PM »

850 T uses Bosch.

Groover · « **Reply #6 on:** October 04, 2016, 03:43:32 PM »

From the diagram, I think he has a combo rectifier/regulator. (not OEM setup).

Tom · « **Reply #7 on:** October 04, 2016, 03:50:51 PM »

Like Wayne says, you still need the dash light working.

Groover · « **Reply #8 on:** October 04, 2016, 03:55:47 PM »

If this helps any... This is basically a quick and dirty diagram of the stock Bosch charging circuit. It's bypassing ignition switch and such, and is shown as the bare-bone diagram on how the charging happens on that system.

Hope that helps:

Testarossa · « **Reply #9 on:** October 04, 2016, 04:22:38 PM »

Quote

Like Wayne says, you still need the dash light working.

The most popular regulator/rectifier from EME doesn't use the charging bulb. Need to see a photo to know what model regulator he has.

Kiwi_Roy · « **Reply #10 on:** October 04, 2016, 11:21:58 PM »

Why don't you tell us what the bike is or was then we might be more help.

Oh now I see 1975 850T
http://www.thisoldtractor.com/guzzi007/schematics/1974_850T_USA.gif
The two yellows and a red threw me off, it should have 3 yellows.

See the blue wire going to 61 of the regulator, that should have a little bit of Voltage on it when you turn the key on and the generator light should be on, this little bit of current supplies the initial field for the alternator, as someone said without the bulb it may not start.
Make sure you have all the wires around the alternator, 3 yellows, red wire from regulator to battery etc. Make sure the regulator (20) has all it's wires and a ground although it may be by the brown wire connected to chassis inside the alternator. The rectifier also needs a good ground.
The alternator Y terminal goes to the rectifier Y terminal not as shown.
Perhaps post some pictures of the various connections and the alternator we may spot something.

luthier · « **Reply #11 on:** October 05, 2016, 07:08:40 AM »

Just get a Greg Bender wiring loom. You'll be so glad you did.

Email Greg and tell him your troubles and he'll tell you to answer a series of questions.

Then he'll make a loom for you with all the right connections and with backup instructions on his website.

Plus he will give personal help and advice if you need it. He is the way and the light with Guzzi electrics.

http://www.thisoldtractor.com/

charlie b · « **Reply #12 on:** October 05, 2016, 07:26:19 AM »

Two yellow wires means it is not the stock setup. I would suspect the reg/rectifier in this setup.

Use this

http://www.electrosport.com/media/pdf/fault-finding-diagram.pdf

Rusnak_322 · « **Reply #13 on:** October 05, 2016, 09:54:57 AM »

Sorry,
I was trying to figure out the brand & model of the combo req/reg. I didn't get a chance last night, I have to remove the tank to get a good look at it. Here is the only picture of it that I could find on my phone.

Can't get a custom wiring harness as nothing on my bike is stock or in the stock place (the reg/req is no longer sitting out like this).

Wayne Orwig · « **Reply #14 on:** October 05, 2016, 10:08:35 AM »

It isn't Bosch or Ducati. I don't suppose you have a picture of the alternator with the cover off?

Groover · « **Reply #15 on:** October 05, 2016, 10:20:05 AM »

I don't recognize the logo, and I googled the numbers I could read from the photo and no luck. I'm out.

Hopefully someone can help you out.

Chuck in Indiana · « **Reply #16 on:** October 05, 2016, 10:53:42 AM »

My bad. I *assumed* it was a Bosch since it was on a T.

Rusnak_322 · « **Reply #17 on:** October 05, 2016, 01:21:14 PM »

took some quick pics at lunch -

There are only three wires coming out the end of the harness and I couldn't feel any more that may have been cut short.

More of the rec/reg

Wayne Orwig · « **Reply #18 on:** October 05, 2016, 01:46:46 PM »

Well, there you have it. A Saprisa system.
I'm out. I know the Bosch and Ducati, but not the Saprisa.

Rusnak_322 · « **Reply #19 on:** October 05, 2016, 02:53:24 PM »

is that "Saprisa" like "Saprisa, your bike, she no longer works!"

Rusnak_322 · « **Reply #20 on:** October 05, 2016, 02:58:09 PM »

searching for the Saprisa alt led me to this post -

http://wildguzzi.com/forum/index.php?topic=30714.0

and this wire dia

http://www.thisoldtractor.com/guzzi007/schematics/1988_1000_SP.gif

Testarossa · « **Reply #21 on:** October 05, 2016, 05:10:53 PM »

So, the PO modified the bike by installing a (late '80s) Saprisa charging system. I acquired the same system when I bought my Mille GT this summer, and have been learning about it.

The Saprisa alternator is brushless, and depends on permanent magnets rather than electromagnets in the rotor. As I understand it, the red wire from battery to alternator energizes the coils in the stator. The two yellow wires then take AC current to the regulator/rectifier. The 1000SP wiring diagram is the one I use for the Mille GT -- it's valid for the charging system, anyway.

The original 850T had an inadequate Bosch 180-watt (13 amp) alternator. Many owners upgraded to the 20-amp (280 watt) Bosch stator used on the T3 and later bikes, which at least would charge the battery at idle with the headlight on. The Saprisa is also rated at 20 amps and seems adequate as long as you keep the revs up. Loaf around town at 2000 rpm and you'll want to keep the headlamp off.

charlie b · « **Reply #22 on:** October 05, 2016, 08:23:56 PM »

You should still be able to use the troubleshooting guide I posted above.

Kiwi_Roy · « **Reply #23 on:** October 06, 2016, 06:38:50 AM »

You came up with gold
http://www.thisoldtractor.com/guzzi007/schematics/1988_1000_SP.gif
The alternator must be a center tapped winding with each yellow going to a SCR diode (are those lugs discoloured from being loose or is it just the picture)
The red/black wire from the fuse to regulator will likely turn it on and also act as the Voltage reference so it should have 12 Volts with the key ON
The black wire I see in your picture must be the regulator ground, it should be just as beefy as the red wire because it carries the same charging current on the return journey.
I'm not sure if the charge light is required on this model but assume you want it anyway.

There seems to be a terminal with no wire on it, I can't make out if it's L.E. or the switch.
Is that an arc mark on the case?

MG Cycle list a regulator but you probably don't need it.
http://www.mgcycle.com/index.php?main_page=product_info&products_id=1038

Kiwi_Roy · « **Reply #24 on:** October 06, 2016, 07:24:46 AM »

If you look at the last post it shows the half wave idea except the diodes will be SCRs (controlled diodes)
L1 L2 are the coils in the alternator with the center point the red wire.

http://www.guzziriders.org/saprissa-regulator-advice_topic2544.html

Rusnak_322 · « **Reply #25 on:** October 12, 2016, 06:18:43 PM »

Thank you everyone for your help.
I went to test it, but my tester died. The battery exploded. I went to Harbor Freight and got another on. Free with the purchase of a $5 pair of work gloves (they also let me use a 20% off coupon)

I started to test it based on the link above last night but had to quit as it was a little late to make noise.

So today I was all set and the stupid tester is on the fritz.

Rereading the posts above I realized I didn't have power to the rectifier. I put a dedicated ground to the frame and while I had the bike running and temporarily hooked up a wire from the rectifier to the hot terminal on the starter. Immediately the headlight got a lot brighter and the off switch wouldn't work. I assume that is the fix? I will wire a permenent hot switched lead.

Rusnak_322 · « **Reply #26 on:** October 12, 2016, 06:21:27 PM »

BTW in the diagram above, that is a fuse between the stator and the positive battery terminal, but what is the circle with the x on the other side, by the switch?

Kiwi_Roy · « **Reply #27 on:** October 12, 2016, 10:08:09 PM »

The Charge light, thats a standard electrical symbol for a small lamp.

The switch is supposed to indicate the ignition switch, you aren't supposed to follow this literally.
See how it's done on this schematic, the two top fuses are fed from the ignition switch by the brown wire and if you trace the wires from the second fuse down you will see it goes to the switch terminal
on the regulator and also the generator light item (10) in a round about way.
http://www.thisoldtractor.com/guzzi007/schematics/1988_1000_SP.gif

So it's all fixed then?

Rusnak_322 · « **Reply #28 on:** October 13, 2016, 08:38:51 AM »

I think so,
Like I said, I had some temp wires, one a ground and one from the regulator to a hot lead and at idle, the headlight got significantly brighter. Once I get a working tester, I can verify.

So, with my stator, I do not have a rectifier, just a regulator? How does the voltage regulator work? Why does it need 12V power to function?

Testarossa · « **Reply #29 on:** October 13, 2016, 12:36:04 PM »

It's a combination rectifier and regulator. Two devices in one box.

News:

Author Topic: quick charging test (Read 9436 times)