Current Drain

[markhouse]

The battery on my 1959 G2 keeps discharging due to a current drain that I have not as yet found the cause. I connected a multimeter between a battery connection and found that something is sinking just over one Amp. I have checked all the simple things, switches, lights etc, but it is still there. Just wondering if anyone else has experienced this and found the problem? Thanks.

[en7jos]

Hi Mark,

Wow, 1A is a big drain! What type of charging system does your bike have? I would guess at some some of problem with the voltage regulator that is causing it to not disconnect the various dynamo / alternator circuits correctly. If it was a faulty circuit (short-circuit, bad switch, etc) then the effects would be more noticeable if it is sinking of an amp.

An easy way to rule out the various light circuits is to remove all of the bulbs. This breaks all those circuits, but I would be surprised if it was a lighting circuit causing your problems. Do you by any chance have electronic ignition fitted? If so, that might be the culprit perhaps.

Let us know how you get on and what you find...
James

[Janet]

Have you checked to see if you have a bit of bare wire somewhere that may be earthing where it didn't oughta? I think this could cause the effect.

[Ozmadman]

I just love wiring

[saltbox alf]

I agree with James, does sound like a regulator problem particually if it's a mechanical one, 1 amp is a lot of drain. it can happen on solid state regulators too, going open circuit.
If it is a short circuit, no doubt some evidence of smoke escaping the wires would be seen.

As you know, lucas electrical systems run on smoke, if you have a chaffed wire touching the frame the smoke will instantly escape!!

[Les Howard]

Hi Remove the connections to the rectifier and test for drain again. Very likely to be the rectifier as it is probably the old original Selenium type? replace with Silicon bridge rectifier....Eg: ....http://www.ebay.co.uk/itm/KBPC2502-25A- ... 1c371e976f
or Maplins...Les

[Ozmadman]

Hi Remove the connections to the rectifier and test for drain again. Very likely to be the rectifier as it is probably the old original Selenium type? replace with Silicon bridge rectifier....Eg: ....http://www.ebay.co.uk/itm/KBPC2502-25A- ... 1c371e976f
or Maplins...Les

Or better still get one of these as this also does away with that resistance wire in the system if you have the original wiring. I fitted one of these about 2 years ago now and it is brilliant, no overcharging/blowing bulbs and you can still use the emergency staring option.

http://www.norbsa02.freeuk.com/goffyelectrex.htm

Paul

[SPRIDDLER]

I hope you have a fuse in the battery 'Live' wire.

(1 amp won't blow it, but if you've a wiring fault that develops further................ )

But what do I know....

[markhouse]

Thank-you for all the replies, it is much appreciated. I shall take them all on board and let you know how I get on. My British Bike status is as follows:

Matchless G2 - Leccy problem.
AJS 14CSR - Leaking gearbox - Thanks ever so much to Colin for providing me with the O-ring seals required.
Triumph Bonneville T120R - Seized clutch.

I have to rely on the weather to be able work on the bikes as I do not have a workshop unfortunately.

[Ozmadman]

I have to rely on the weather to be able work on the bikes as I do not have a workshop unfortunately.

Snap, but no excuses at the moment!!! I have finished my Yamaha during this hot spell, not AMC but here's a picture anyway