Ticking Voltage Regulator

[Zack]

Hi all,
I'm having a bit of an issue with my voltage regulator but I don't know if I should be worried about it or not! about 2 months ago the generator on my '68 died so I replaced it with a new one and a new voltage regulator at the same time. Everything worked well until about 2 weeks ago when the batter wouldn't charge - it was 7 years old so I replaced it. So now I have a brand new VR, Generator & Battery.

The problem I'm having is that when I drive (and the engine is off idle) I can hear the voltage regulator constantly ticking loudly and the red ignition light on the dash flashes in time with the ticks from the voltage regulator. This started right before the old battery died. I swapped the VR for a known good one with no difference in the tick-tick-tick-ticking. Is this normal or does it mean my battery isn't charging? I never noticed the VR ticking or the ignition light flashing before I replaced the generator. Thanks

[bmcecosse]

No - this is not normal - and yes it could mean not charging. In all these swaps - did you change the polarity of the battery earthing at all ? You say it's same with another VR - and I can't see how it can be the dynamo - so I would suspect poor connections - especially the earth connection for the VR. Can you get a voltage reading at the battery when the engine is doing reasonable (ie not idling) revs ?

BTW -This should really be in Electrical section!

[Zack]

Oh sorry about posting in the wrong forum - a moderator can move this thread if possible.

Thanks for the advice - I did not change the polarity of the battery, but the car has been converted to Neg. Earth at some point.

The dynamo seems to be charging well as I'm getting 13.5v across the battery terminals with the engine off idle. I will clean & check the connections on the VR on my lunch break today.

[bmcecosse]

Aye - well it is certainly putting some juice into the battery - so that really means the dynamo is ok too. Really only leaves connections!

[Zack]

Well I was just out and cleaned all the contacts on the VR and cleaned the ground on the battery without any change. It's still tick-tick-tick ticking and the ignition light is flashing along in time.

I think I'm going to try adding an additional ground to the VR after work and see if that helps.

[mike.perry]

Take the cover off the control box and watch the contacts when you rev the engine. The contact on the short bobbin should close when you you rev the engine and open when the engine is on slow tickover or switched off. It should not open and close when the engine is running. The ignition light should shine when the contacts are open and go out when the contacts are closed.
Silly question time
Are you sure that the ticking noise is not the fuel pump?
Are you sure that the bulbs in the speedometer are in the correct places, the igniton in the red lens and the low oil pressure in the orange lens? (On a 1098 black speedo)

[bmcecosse]

If you look at the wiring diagram here http://www.mmoc.org.uk/viewtopic.php?f=11&t=28295 you will see the VR needs a good earth connection. Rig up an additional earth from the VR terminal back to the battery to see if that cures anything!

[Zack]

Well I cleaned all the contacts last night and rigged up an extra ground to the VR without any change. I'm still getting ticks from it about twice a second when the engine is above idle, and the ignition light is flashing in time with the ticks.

Take the cover off the control box and watch the contacts when you rev the engine. The contact on the short bobbin should close when you you rev the engine and open when the engine is on slow tickover or switched off. It should not open and close when the engine is running. The ignition light should shine when the contacts are open and go out when the contacts are closed.

I took the cover off the control box last night and watched the bobbins as you've suggested Mike - the short bobbin is open at idle, and when the engine is revved it opens and closes about twice a second. Seems that something is still wrong - could the generator be causing the problem? I have a '65 MGB and I think the generators are interchangeable - could try swapping them out to see if there is an effect.

Silly question time
Are you sure that the ticking noise is not the fuel pump?
Are you sure that the bulbs in the speedometer are in the correct places, the igniton in the red lens and the low oil pressure in the orange lens? (On a 1098 black speedo)

Thanks for the suggestions, but I am sure it is the voltage regulator making the noise and flashing the light as I can see the contacts on the bobbin opening and closing in time.

So next I'll try swapping the generator? any other ideas? I've never heard anyone having this sort of problem before so it's a little harder to figure out where to go.

Thanks

[Zack]

This is the regulator I'm using

It was listed for an MG Midget 1098, but I assumed they're the same - the terminals are marked the same and my wiring all fit properly.

Could it be mis-adjusted somehow?

[bmcecosse]

It's the right unit - and you say another does exactly the same - so can't be the VR! I would think unlikely to be the dynamo - your volts are up, so it is charging - but by all means try a swap. Possible the wires on the VR are not connected as per diagram ? have you checked the actual colours of the wires against Barry's diagram ?? Just one other try - what happens if you switch on the headlights ?

[Zack]

I checked against the wiring diagram and everything is connected correctly and the colours are 100% correct.

I've been driving the car for a couple days and haven't been stranded yet, so apparently there is enough charge getting through to keep me going. There is no change with the headlights on or off.

I talked to the vendor where I got the regulator earlier today and he is going to call around and see if he can come up with an ideas. Check to see if there were any other reported problems with regulators from the same batch etc etc.

At this point I'm going to swap over the generator from my MGB (provided it will fit) and see if that makes a difference. I suppose it's possible both the new regulators are bad, but somewhat unlikely.

[mike.perry]

You could try swapping the control box onto the MGB, you don't have to fix it on, just connect the wires and let it hang somewhere safe whilst you check it out. That would also eliminate any wiring problems.

[bmcecosse]

It's a fault I haven't come across before! And you say it's there with two regulators - so hard to believe they can both have an obscure fault. However - you seem to have tried everything - time for a good reliable alternator I think!

[PSL184]

It is certainly a strange fault - You haven't accidentally wired it through the flasher relay have you

[bmcecosse]

This happened with the old battery - before you changed the dynamo and the regulator - and still continues - with new VR, new dynamo and new battery. So really - it HAS to be a wiring issue somehow!

[Zack]

It's a fault I haven't come across before! And you say it's there with two regulators - so hard to believe they can both have an obscure fault. However - you seem to have tried everything - time for a good reliable alternator I think!

Thanks for all the advice everyone, this is really a head scratcher for me too. I've double and triple checked the wiring last night and it is all correct (not through the flasher relay!) and the terminals are clean. The fault has continued through 2 Voltage Regulators and 2 batteries, so at this point I'm thinking (hoping) it's the generator. The generator on the MGB appears to be the same so I will try swapping it over this weekend, unfortunately the VR for the MGB is a different style and doesnt' appear to be interchangeable without wiring modifications.

Aside from the generator the wiring could still have a bad connection or ground somehow but it is a little strange that the new generator/voltage regulator would have functioned well together for a month before the fault developed.

Here's my plan of action for this weekend:
1. Swap known good generator from MGB over and test drive
2. If that doesn't work spend more time cleaning the wiring
3. Try to locate a known good VR to test (it could be a bad batch of VR I suppose)
4. If none of that works I'll start looking at Alternator conversion kits!

[mike.perry]

You know that the MGB is ok so swap the regulator from the Minor onto the MG. That way if you get still get the problem it must be the regulator since that is the only suspect component. If there is no problem then you have definately eliminated the regulator, you can then fit the Minor dynamo onto the MG and the same rules apply. That just leaves the wiring, check that there are no worn bits shorting out and that the fuse box connections are all secure.

[bmcecosse]

Just to check - nothing else has changed - no additions to the car's electrical system ?? And you are SURE the polarity hasn't been reversed ?

[Zack]

You know that the MGB is ok so swap the regulator from the Minor onto the MG. That way if you get still get the problem it must be the regulator since that is the only suspect component. If the is no problem then you have definately eliminated the regulator, you can then fit the Minor dynamo onto the MG and the same rules apply. That just leaves the wiring, check that there are no worn bits shorting out and that the fuse box connections are all secure.

Okay Mike that sounds like the best way to go about it. I probably won't have any time to work on the cars until Sunday but I will certainly update this thread with the results so I don't keep you guys hangin!

Again, thanks for all the advice, it helps to have a number of minds working on strange problems like this.

[mike.perry]

A good way to look for faulty cables is to run the engine in the dark and look for any sparks in strange places