guzziriders.org - moto guzzi forum Homepage
Forum Home Forum Home > Technical > Loop Frames
  New Posts New Posts RSS Feed - V7 850 GT not charging
  FAQ FAQ  Forum Search   Events   Register Register  Login Login

V7 850 GT not charging

 Post Reply Post Reply Page  <123
Author
Message
Dave P. View Drop Down
Senior Member
Senior Member
Avatar

Joined: 12 Jan 2015
Location: Northants
Status: Offline
Points: 5573
Post Options Post Options   Thanks (0) Thanks(0)   Quote Dave P. Quote  Post ReplyReply Direct Link To This Post Posted: 15 Feb 2019 at 17:37
Have you cleaned/brightened all the terminals/connectors? Battery terminals and battery earth to frame?
The next step would be to check the dynamos' none regulated output.If that is OK then I would think the regulator may be to blame.An auto electrician can test and if required adjust it for you.You would have to take it off the bike.You could also take the dynamo in for testing.


Edited by Dave P. - 15 Feb 2019 at 17:41
TO LIVE OUTSIDE THE LAW YOU MUST BE HONEST.

1971 V7 Special. 1972 850GT.
1970 T120 Bonnie. 2009 500 Bullet.
Back to Top
el__burro View Drop Down
Senior Member
Senior Member
Avatar

Joined: 04 Aug 2018
Location: London UK
Status: Offline
Points: 423
Post Options Post Options   Thanks (0) Thanks(0)   Quote el__burro Quote  Post ReplyReply Direct Link To This Post Posted: 15 Feb 2019 at 18:41
Originally posted by Dave P. Dave P. wrote:

Have you cleaned/brightened all the terminals/connectors? Battery terminals and battery earth to frame?
The next step would be to check the dynamos' none regulated output.If that is OK then I would think the regulator may be to blame.An auto electrician can test and if required adjust it for you.You would have to take it off the bike.You could also take the dynamo in for testing.
Yes, all terminals cleaned.
How would i rate the Dynamo output?
thanks
el__burro
Back to Top
Mike H View Drop Down
Senior Member
Senior Member
Avatar

Joined: 21 May 2014
Location: East Anglia
Status: Offline
Points: 8733
Post Options Post Options   Thanks (0) Thanks(0)   Quote Mike H Quote  Post ReplyReply Direct Link To This Post Posted: 15 Feb 2019 at 21:44
Mind you 13.5V is not that bad. Are you sure that isn't what it's supposed to be?


"Chicken nuggets don't dance on a Tuesday."
Back to Top
Dave P. View Drop Down
Senior Member
Senior Member
Avatar

Joined: 12 Jan 2015
Location: Northants
Status: Offline
Points: 5573
Post Options Post Options   Thanks (0) Thanks(0)   Quote Dave P. Quote  Post ReplyReply Direct Link To This Post Posted: 16 Feb 2019 at 08:02
According to the book Mike, 13.8V to 14.5V.
TO LIVE OUTSIDE THE LAW YOU MUST BE HONEST.

1971 V7 Special. 1972 850GT.
1970 T120 Bonnie. 2009 500 Bullet.
Back to Top
Dave P. View Drop Down
Senior Member
Senior Member
Avatar

Joined: 12 Jan 2015
Location: Northants
Status: Offline
Points: 5573
Post Options Post Options   Thanks (0) Thanks(0)   Quote Dave P. Quote  Post ReplyReply Direct Link To This Post Posted: 16 Feb 2019 at 11:41
To test the dynamo do the following;

Disconnect all three leads from the dynamo.

Connect the D+ and F terminals together with another piece of wire.

Connect the positive lead of your voltmeter to D+ and the negative lead to a good earth on the bike.

Start the engine and briefly run it at around 1000 RPM.

A good dynamo should give a minimum reading of 14V.

If you rev' it harder the reading will increase,but don't do it or you could risk damaging the dynamo.

I must emphasize that running the dynamo without the regulator must be done BRIEFLY.

Edited by Dave P. - 16 Feb 2019 at 11:44
TO LIVE OUTSIDE THE LAW YOU MUST BE HONEST.

1971 V7 Special. 1972 850GT.
1970 T120 Bonnie. 2009 500 Bullet.
Back to Top
Mike H View Drop Down
Senior Member
Senior Member
Avatar

Joined: 21 May 2014
Location: East Anglia
Status: Offline
Points: 8733
Post Options Post Options   Thanks (0) Thanks(0)   Quote Mike H Quote  Post ReplyReply Direct Link To This Post Posted: 17 Feb 2019 at 16:29
Originally posted by Dave P. Dave P. wrote:

According to the book Mike, 13.8V to 14.5V.


OK, next question, how accurate is the Voltmeter ... Big smile


"Chicken nuggets don't dance on a Tuesday."
Back to Top
Dave P. View Drop Down
Senior Member
Senior Member
Avatar

Joined: 12 Jan 2015
Location: Northants
Status: Offline
Points: 5573
Post Options Post Options   Thanks (0) Thanks(0)   Quote Dave P. Quote  Post ReplyReply Direct Link To This Post Posted: 17 Feb 2019 at 19:04
Ahaa! Good question Mike. Other than comparing the readings of my digital meter with those of my analogue meters I don't know.
Please advise.

Edited by Dave P. - 17 Feb 2019 at 19:34
TO LIVE OUTSIDE THE LAW YOU MUST BE HONEST.

1971 V7 Special. 1972 850GT.
1970 T120 Bonnie. 2009 500 Bullet.
Back to Top
jefrs View Drop Down
Senior Member
Senior Member
Avatar

Joined: 12 Aug 2018
Location: West Berkshire
Status: Offline
Points: 333
Post Options Post Options   Thanks (0) Thanks(0)   Quote jefrs Quote  Post ReplyReply Direct Link To This Post Posted: 17 Feb 2019 at 19:14
Not have had  a problem with the Guzzi but recently on Goldwing and Enfield EFI when the batteries were going flat for no good reason.

The GL1800 seems to have been traced to two always-on dip beam H7 that were both blown (weird) and probably shorting, anyway fixing them stopped the 5A that was being constantly drawn. We're kinda at a loss to explain this one, it comes under the "have you tried kicking it?" category, or as NASA had it, "assist with lunar boot".

On the Enfield even weirder because the battery tested 'good' by the man that sells batteries on his fancy battery tester but as soon as a small current was drawn it would drop to 12.2V or less. Small current like 1.7A which is the ECU and fuel pump etc. Which is unhelpful for the electric starter.  Charging at 14.4V on the bike, which is correct here, would soon have it up to 12.8V, but then it would fall slowly when switched off. My test meter is a Fluke. 
Battery tests good but is not holding charge and can't sustain current.  There is current available, enough to turn the engine over, but not at the right voltage.  New one pickling down on the bench. We discovered that if you don't let them pickle, when you pull charge off they can froth up and dribble 10 molar acid onto chromed Honda exhaust.

Point - battery faults are not always the most obvious. This is Sod's Law.
Back to Top
Brian UK View Drop Down
Moderator Group
Moderator Group
Avatar

Joined: 13 May 2014
Location: Surrey
Status: Offline
Points: 17641
Post Options Post Options   Thanks (0) Thanks(0)   Quote Brian UK Quote  Post ReplyReply Direct Link To This Post Posted: 17 Feb 2019 at 22:08
I think Mr Ohm's second name was Sod.

The Enfield battery was just well past it's best. Fairly typical of a dying battery.

Iv'e seen this recently on a 2.5 year old car battery. Showed good voltage, charged ok too, but as soon as any load was put on it the voltage dropped drastically. It does make me ask what test the battery seller did with his posh tester.



Edited by Brian UK - 17 Feb 2019 at 22:14
Brian.

Better 5 minutes late in this world than years early in the next.
Back to Top
Mike H View Drop Down
Senior Member
Senior Member
Avatar

Joined: 21 May 2014
Location: East Anglia
Status: Offline
Points: 8733
Post Options Post Options   Thanks (0) Thanks(0)   Quote Mike H Quote  Post ReplyReply Direct Link To This Post Posted: 18 Feb 2019 at 21:52
Originally posted by Dave P. Dave P. wrote:

Ahaa! Good question Mike. Other than comparing the readings of my digital meter with those of my analogue meters I don't know.
Please advise.


One would hope a new PP3 battery would be good for a reasonably accurate 9 Volts.


"Chicken nuggets don't dance on a Tuesday."
Back to Top
Brian UK View Drop Down
Moderator Group
Moderator Group
Avatar

Joined: 13 May 2014
Location: Surrey
Status: Offline
Points: 17641
Post Options Post Options   Thanks (0) Thanks(0)   Quote Brian UK Quote  Post ReplyReply Direct Link To This Post Posted: 18 Feb 2019 at 22:10
Ever checked a new AA cell? Never shows 1.5 volts.

Most digital meters are pretty accurate. I have three, and all read the same, provided the internal battery is good. The analogue one can't be read with the same accuracy.

I only have cheap meters, well actually the analogue was quite a good spec when I bought it 40 years ago.
Brian.

Better 5 minutes late in this world than years early in the next.
Back to Top
c13pep View Drop Down
Senior Member
Senior Member
Avatar

Joined: 31 Aug 2017
Location: Doncaster
Status: Offline
Points: 2110
Post Options Post Options   Thanks (0) Thanks(0)   Quote c13pep Quote  Post ReplyReply Direct Link To This Post Posted: 19 Feb 2019 at 09:05
Originally posted by Brian UK Brian UK wrote:


I only have cheap meters, well actually the analogue was quite a good spec when I bought it 40 years ago.


Much like my wife says about me then

CHRIS
you can`t have any fun in a straight line

Monza
Honda CB77 project

Back to Top
 Post Reply Post Reply Page  <123
  Share Topic   

Forum Jump Forum Permissions View Drop Down

Forum Software by Web Wiz Forums® version 12.03
Copyright ©2001-2019 Web Wiz Ltd.

This page was generated in 0.109 seconds.