Charging system kaput, 1100 Quota

[JayDee24ca]

I took the Q out for the first time this year yesterday. I did a bit of work on it last winter, including installing  Voltmeter and OP gauges. After a few miles I noticed that the voltmeter was reading about 11 Volts, and over the next few miles it got progressively lower. I headed for home, and just about a mile from home, at 10 volts, the tachometer needle started dropping. In about 10 seconds the tach was not registering at all.
Once home I (just) started the bike, and put a digital meter between ground and the positive battery terminal, where it registered only 12 volts charging.
The back story is that two years ago I bought a new Yuasa battery, as the malfunctioning charging system had fried the old battery, charging at 16.5V. I replaced the Japanese regulator/rectifier with one from Euroelectric, which brought the charging down to 13.5V. Everything seemed good when I shut things down for last winter. So, apparently things got corrupted last winter in storage, either through some modification that I did, or through a battery that has been discharged to many times (if I don't keep a tender on it, the battery discharges to 10 volts in about 4 days).
I am looking for suggestions as to where to start. How do i determine if this rectifier is still good, or if the alternator is shot? I hate to simply start throwing new parts at it. I need to find what the problem is though some sort of diagnosis.
Thanks
JD

[fotoguzzi]

Load test battery first. please.

[ITSec]

Load test battery first. please.

 :1:

This.  You can't troubleshoot this problem without first eliminating the simplest and most likely to fail component.

[Chuck in Indiana]

the battery discharges to 10 volts in about 4 days)

"She's dead, Jim.." 

[Kiwi_Roy]

Is the new regulator wired to the headlight like the OEM
The alternator will put out about 60 Volts at 2000 revs on the two yellow wires.
Did you by chance disconnect the regulator over the winter?

[charlie b]

Yep, battery first.

Is the alternator original.  Mine died last year at around 80k miles.  Darn things don't last at all.  Only 32yrs and 80k miles  :)

[JayDee24ca]

Battery charged to 12.5. Tested between positive post and frame ground, with ignition and lights on (surface charge removed), it reads 12.25V. Then tested between a point upstream from the positive post and the same frame ground, (in order to ascertain good battery connections)and no difference in readings were seen.
How is the tach associated with a non-charging situation? Or are there two separate issues here?
Thanks
JD

[fotoguzzi]

Battery charged to 12.5. Tested between positive post and frame ground

that's meaningless.. take it to batteries plus and have a load test done.

[scra99tch]

Not that this will help in anyway, but behind the plate on the fuse block side the wire loom has a dip in it as it travels from fuse block to triple tree.  In this dip moisture collected and degraded several factory splices.  I was not experiencing any of your symptoms but just giving it a mention.

[Kiwi_Roy]

How is the tach associated with a non-charging situation? Or are there two separate issues here?
Thanks
JD

The OEM Ducatti Energia regulator taps into the red/black wire feeding the headlight, that also supplies the tacho but you have an after-market regulator
I don't know if it also uses the Red/Black feed but any time the tach or headlight's not working I suspect it's not charging either.
Make sure you have a 5 pin relay in the start relay slot.
Post the model No of the regulator.

[JayDee24ca]

The OEM Ducatti Energia regulator taps into the red/black wire feeding the headlight, that also supplies the tacho but you have an after-market regulator
I don't know if it also uses the Red/Black feed but any time the tach or headlight's not working I suspect it's not charging either.
Make sure you have a 5 pin relay in the start relay slot.
Post the model No of the regulator.

Roy, the Reg/Rect I  used is an Enduralast from Euro Motoelectrics, model ELDGUZ-VoltRectOE. Here is a link. http://www.euromotoelectrics.com/product-p/edlguz-voltrectoe.htm
I do have a 5 pin relay on the start circuit.


As to the load test on the battery, I will see if there is anyone in this town that can perform that test. There are not a lot of choices here, and that is why I tried to provide what limited information I have, as to the state of the battery. 
JD

[Kiwi_Roy]

The male part of the male/female plug is where the regulator get's it's power from plug
It's labeled Black Rectifier Power

http://www.euromotoelectrics.com/product-p/edlguz-voltrectoe.htm

Looking at Carl's drawing the rectifier (regulator) (18) is shown at the bottom, the m/fm plug is the two right most wires, the red/black one is the one we are interested in
it gets power from the headlight relay (29), With the key On you should see 12Volts to chassis, no 12 Volts = no charging.
While you are there unplug the rectifiers red wire, the socket it plugs into should also be alive.
Unplug the two yellow wires, check the Ohms between the sockets (alternator coils) < 0.5 Ohms?
With the engine running you will get AC Volts on the yellow wire sockets 10 - 60 Volts depending on revs.

http://www.thisoldtractor.com/guzzi007/schematics/2000_Quota_1100_ES.gif
Note: Guzzis don't always follow the drawing exactly, there may be a 30 Amp fuse in the red wire, if so examine it closely for any discolouration of the plastic caused by loose contact.
This early drawing shows the headlight relay terminal 30 fed from the start relay 87A, this might have changed on your bike.