Leaking Voltage at Battery Earth

[Supaflee]

This is annoying me somewhat .
Since I've had the bike, the ignition alternator/charging lamp has not glowed when I switch the ignition on.( the bulb is good )
Lately I've noticed my Battery slowly dying over about a week . I had a load test done on the battery , it's as good as new when fully charged . Plenty of energy there and meets the expected specifications for the 32A/hr Battery.
Yesterday it was flat yet again , so , once more I changed it fully.
Today I went to connect the Bike's battery leads up again , and I did a voltage leak test between the Battery Earth terminal and the Earth lead . Ignition switched OFF . There is 2.34 volts leaking to "somewhere" in the system.
So, what do you think is happening?? I cannot seem to obtain a current reading though ( weird I thought )
My bike has Dyna 111 Electronic ignition fitted.
Im wondering if there is a stuffed diode somewhere----------that would cause it , ,,,,wouldnt it ??
Thanks Supaflee

 

[draidt]

Digital or analog meter ?

 

[john zibell]

What you have is called a parasitic drain. Instead of a volt meter, use an amp meter. Best would be a multimeter that can read mili amps. Connected it on the positive side of the battery. If you have multiple connections, connect one at a time through the amp meter to determine which line has the draw. Once you determine the line that has the draw, isolate components on that line until you have eliminated the draw, then you will have found the offending component.

 

[geodoc]

I just had this mystery flat battery situation on my 2001 Triumph Sprint RS. That one was to an extent self-induced. I installed a electric vest plug with a switch-operated relay. I accidentally left the switch in the 'on' position and the draw flattened the battery in the 2 weeks between rides. Turns out the battery was on its last legs too.

In troubleshooting that I discovered that with the ignition and accy. plug switch off the bike has a 1.6 ma draw. I tracked it down to the instruments power circuit. There is also some sort of power connection between the instruments and the ECU. Anyway, one of those components is drawing 1.6 ma. I wonder, is a small load like that normal in fuel injection systems for some 'keep alive' function?

As an aside, I use the negative side of the battery to make this test. Suppose it doesn't really matter for the test, but it makes it so you don't get accidental grounding of the positive lead with sparks, etc.

GD

What you have is called a parasitic drain. Instead of a volt meter, use an amp meter. Best would be a multimeter that can read mili amps. Connected it on the positive side of the battery. If you have multiple connections, connect one at a time through the amp meter to determine which line has the draw. Once you determine the line that has the draw, isolate components on that line until you have eliminated the draw, then you will have found the offending component.

 

[draidt]

I just had this mystery flat battery situation on my 2001 Triumph Sprint RS. That one was to an extent self-induced. I installed a electric vest plug with a switch-operated relay. I accidentally left the switch in the 'on' position and the draw flattened the battery in the 2 weeks between rides. Turns out the battery was on its last legs too.

In troubleshooting that I discovered that with the ignition and accy. plug switch off the bike has a 1.6 ma draw. I tracked it down to the instruments power circuit. There is also some sort of power connection between the instruments and the ECU. Anyway, one of those components is drawing 1.6 ma. I wonder, is a small load like that normal in fuel injection systems for some 'keep alive' function?

As an aside, I use the negative side of the battery to make this test. Suppose it doesn't really matter for the test, but it makes it so you don't get accidental grounding of the positive lead with sparks, etc.

GD

What you have is called a parasitic drain. Instead of a volt meter, use an amp meter. Best would be a multimeter that can read mili amps. Connected it on the positive side of the battery. If you have multiple connections, connect one at a time through the amp meter to determine which line has the draw. Once you determine the line that has the draw, isolate components on that line until you have eliminated the draw, then you will have found the offending component.

Normal for a modern EFI bike maintains ECU functions and clock otherwise every time you turn on the key the ECU has to reboot and the clock reset, at least for a Marelli system

 

[geodoc]

I suspected such.

Seems odd in a way though. The only "keep alive" function like this that I have any real experience with is aircraft avionics where there's a little battery built-in that "keeps alive" time, last position, display settings, etc. and is charged when the system is connected to aircraft power. Otherwise, it's off like as regards to external power and discharges to the extent necessary to perform its 'keep alive' function.

I've heard that some modern vehicles have to get a fair bit of system re-set when the battery is disconnected and so would appear to not have its own 'keep alive' battery.

Mysterious ..........................

Normal for a modern EFI bike maintains ECU functions and clock otherwise every time you turn on the key the ECU has to reboot and the clock reset, at least for a Marelli system

 

[john zibell]

Guys,

You are drifting this thread off topic. The guy has a Tonti bike with a Dyna III, which means, no ECU and such. With the key off nothing has power and there should be no drain.

 

[Supaflee]

Thanks so far to the input Guys.
Just in answer to draidt's question , "analogue or digital meter "? It's digital.
I've made a couple of interesting findings.
1) I was not aware that the ignition circuit to the key switch is not fused. I looked at Craigs wiring drawings and sure enough , it aint. ( I used the '83 sp11 diagram)
2) At my battery's positive, there are two leads siamesed together under the head of the termination bolt . One lead is heavy , the other is a lot lighter . The heavy lead goes down to the starter solenoid , there is no leakage to it . The lighter lead has leakage to it and is the red wire which goes as the positive feed to the ignition switch .
3) With the ignition switch OFF there is leakage to it of 2.34 volts (digital ) but i cannot get a "Milliamp" reading ??? Why is this .
4) I'm suspecting there is leakage inside the ignition switch caused by the ingress of crud and washing detergent from pressure washers etc and , CRC , over the life of the bike , remember she's a 1985 , started life in Italy ,waddya reckon about that?
5) Then I cut my hand , now its got too dark , and Im dropping stuff , so Im finished till tomorrow .
Huge thanks to all of you out there , Supaflee

 

[john zibell]

3) With the ignition switch OFF there is leakage to it of 2.34 volts (digital ) but i cannot get a "Milliamp" reading ??? Why is this .

Amp meters are installed in series as part of a circuit, volt meters in parallel. Maybe incorrect setup or the meter is not sensitive enough.

 

[Supaflee]

Not to be outdone by this darned "leak", I removed the ignition switch from the bike . :mrgreen:
Because it is a completely sealed unit with exception of the key slot in the uppermost point , I reckon poop has got inside , become conductive , and allowed some voltage to leak across it .( It had an external appearance of having fairly recently been lubricated with something ) .
I soaked it in a jar of CRC Contact Cleaner for 10 minutes . Then I crimped a hunk of galvanised 10 gauge wire to it and while it was submerged , and upsidedown , I shook hell out of it. Enough black crud came out of it to build another island in the Caribean . Wow , unbelieveable !
Just to finish it , ( nothing to lose ), I stuffed the CRC squirty tube right inside the key slot and and gave it about 1/4 tin of contact cleaner under pressure............... its clean in there now .
My digital meter now reads zero .There is no leakage ( continuity ) across the key switch now when it is switched OFF now .
I believe I've found and fixed the leak :evil: .
Just on another note , I also noticed the output wire from the rectifier had a "hot" (poor) crimp connection on the spade , so I soldered that connection whilst I was in fix-it mode.
I think this just about brings me to the useful end of this thread . However, if there are aspects of what I've done , that you wish to discuss more, please dont hesitate to continue the thread .
I still havn't been able to answer why I couldnt get any milliamps as the leaking current at the key switch :angry: .
Best regards Supaflee

 

[Kevin.NZ]

Supaflee, The current ranges on a meter are generally protected by an internal fuse, check yours isn't blown.
Kevin

 

[Chris R]

Because it is a completely sealed unit with exception of the key slot in the uppermost point , I reckon poop has got inside , become conductive , and allowed some voltage to leak across it

Beware 'dielectric' grease (which in this case it is more likely water getting inside). Real 'dielectric' grease as the name implies would be a conductor in metal to metal connections and an insulator otherwise. The grease sold for HV ignition connections is better termed conductive grease and it is a great way to create a short as my friend discovered when he merrily used it for all the electrical connections on his Lambourghini Countach. Use White lithium grease instead - that is what the OEMs use.

The old tonti switches could be taken apart and cleaned by bending some tangs - just watch out for the little spring. I also drill a wee hole to let any water out and allows flushing with contact cleaner.

 

[scottmastrocinque]

...while it was submerged , and upsidedown , I shook hell out of it. Enough black crud came out of it to build another island in the Caribean . Wow , unbelieveable ...

I'll bet you somebody previously shot a bunch of graphite powder lock lube into it. Seen this lots before with the same problems you experienced.

 

[rbm]

3) With the ignition switch OFF there is leakage to it of 2.34 volts (digital ) but i cannot get a "Milliamp" reading ??? Why is this .

Supaflee, I assume you used the same measurement points as described in your first post -- Battery earth connector to Earth terminal on the bike. Is that correct? I also assume that you just changed the function on your multimeter while testing from Volts to Amps (or Milliamps) without changing anything else in your setup. Is that also correct?

If this is the process you followed, the explanation is this. You were measuring the voltage dropped across the earthing wire when you measured 2.34V. There is internal resistance in wiring and any current flowing through a resistor will display a voltage drop proportional to the current drawn. In this case, your leakage current manifested as a drop in voltage across an earthing wire.

If you then changed the function on your multimeter from Volts to Current without changing the test points, you failed to measure any current. The result you saw was zero on the display. As pointed out earlier, you would have also had to change your test points in conjunction with changing the function on your meter. In this case, you should have (1) removed the earth wire from the battery, (2) changed the function on the multimeter to Current and (3) measured the current flowing through the Battery earth terminal and the now disconnected wire. Then you would have gotten a reading.

By the way, voltage doesn't leak; current leaks. Voltage drops. It's a minor observarion but you did get your point across, and apparently your problem solved. Congrats.

 

[Rafael]

Yahoo! back to normal.

But these switches don't last forever. From your description graphite lube was the likely culprit but the switch could be wearing out. I used a rubber band once to hot wire my T-3 while my ignition switch was on order. You might want to have one handy if your ign. switch craps out on the road. The rubber band also acts as an insulator to prevent shorting to the frame.

 

[Supaflee]

This now has just gotten a whole lot "interestinger". ( Kiwi for, "got me buggered" ) :lol:
I thought I'd fixed the battery leakage problem ,so , today with a tank full of gas , and the sun shining favourably on my shoulders , I blasted off.
Well , for a short time anyway. Then I stopped blasting and the swearing started . I'm not able to spell some of the biggies that I used , but they were all in there as a mixture, believe me .
Yep , flat battery. Switched the lights off and limped home after a running start , and checked the battery voltage , 12.1Volts with the engine running . No change to Voltage when I revved it up .
So I have a charging problem ( which I dont think I had before ). :?:
I'll report again after the weekend , hopefully by then I will have isloated the problem and fixed it as well.
Oh , ps , Thanks "rbm" ,The diagnosis you suggest is exactly what I had done . I only established the resistance in the earth lead ,as "voltage" like you say . In answer to your questions in your second paragraph , Yes.
Whew , I wonder what to check now as a starting point for no charging. I've certainly established there is no charge getting to the Battery ,,,,,,,,any tips for this will be greatly appreciated .
On a nice note , Im loving my Guzzi.Today was the first time I've given it any sort of a handful , revved her out to about 5000 through 3rd , 4th , into 5th , corrrrrrrrrrr she sounds beautiful. She's got reverse cone SS mufflers , a lot like a Commando but with 40mm(1.5") bore glass packed around perforated tube .
Supaflee

 

[john zibell]

Which charging system do you have, or bike?

 

[Supaflee]

Hi John.The Bike is a 1985 SP11. 1000cc . I think the engine has been optimised for performance as it goes like hell for an older technology engine :huh: .
The electrics are standard , apart from a Dyna 111 ignition . My bike does not have a clock, fuel meter , voltmeter . I've been viewing Carl's electrical drawings in the Tech Index , and using the wiring diagram for 1983 SP 11.
I'm not sure how to answer your second question , as I thought they all had the same charging system.
Alternator, rectifier , regulator , battery -----------------now im just assuming this , as this is the extent of my knowlege of bike charging systems .
I hope I've given you enough of a heads up to help me yet further , John.
Regards Supaflee

 

[OldJock]

Probably a Bosch charging system then, with 3 phase charge and variable voltage output via the field electromagnet.

Guzzi then moved to a Saprisa 2 phase fixed output generator. I don't know the newer bikes after that. The thing is these systems although they all have the parts you mention work in different ways.

Do you have a charge light on the bike or generator warning light if you prefer and does it go out above approx 1500 RPM?

If the charge light bulb has burnt out, there is a good chance that the charge system will never start. You need that bulb to work. If you don't have the light then a PO must have installed a resistor or something which you'll need to find to check. I just found it suspicious that you made no mention of the light at all and the system is not working.

If you don't have the charge light could you post a picture of the regulator and rectifier? I am just wondering if a PO may have installed an aftermarket system and often these do away with the charge light.

After the bulb I'd check that all your connections are good on generator, rectifier and regulator. Posting up a couple of pictures of your generator, rectifier and regulator again will help people check the connections. Check the brushes on the generator are not worn and spring back onto the slip rings freely and the rings are not covered in muck. Of course battery earth too (although that usually leads to overvoltage rather than none)

After that there are some pretty simple tests that can be done to narrow it down some more. But that's where I'd start first.

I wrote an article which contains an explanation (but is a work in progress) just look at the charge circuit

http://www.thisoldtractor.com/guzzitech.dk/pdf/charging-around-the-circuit-john-noble.pdf

A good explanation on the system is also here, its for BMW airheads but the system is the same

http://www.ibmwr.org/r-tech/airheads/charge.shtml

John

 

[john zibell]

Supaflee,

Old Jock's post is accurate. You do have the Bosch system. The bulb must work for the charging system to operate. The highest rate failure item after the bulb is the rotor. Check that you have about 3 ohms or so from ring to ring. If an open circuit, the system won't charge and the bulb can't illuminate. Also disconnect the leads from the brushes and make sure there is continuity from the ground (D-) to the power connection (D+) from the voltage regulator at the stator. If the bulb does light when you turn the key on, you can jumper the two leads of the connection to the voltage regulator that are parallel (they should have the same color wires attached), but only run the bike briefly as you can over charge the battery. If the bulb goes out, the regulator is faulty, if not, stator is usually at fault, or possibly the rotor isn't producing an adequate magnetic field.