I'm Baffled

It's time to be methodical.

All this is with the battery connected.

Put the meter on volts and connect one end to earth (I'd use the engine). Then go through the wiring looking for voltage. I find it easiest to do a "binary chop" ie start mid way through a circuit. So in your case I would look for a voltage at the input side of the ignition switch. If it's showing full voltage (12.6+) then switch it on and see if it still shows the same (or it should be slightly less). If it disappears when switched on the battery is suspect. If it doesn't drop at all then there switch isn't working or there's a break downstream. Is the voltage showing on the switched side? If yes, the switch is OK; if no it's the switch, Carry on like this, checking for voltage throughout the system.

It can help to make notes of everything you do as it's easy to forget / get confused.

I find electrics quite straightforward but the problem is you can't see voltage or current so need instruments. If you have Fluke meter then you're better equipped than most.

Dear Malcolm.

Test the old fashoned way using an indicator bulb in a bulb holder with 2 flying leads a couple of feet long. Check it works on a car battery before you start. then test progressively;

Does it light across battery? if not battery at fault

Does it light with one lead on negative battery and one lead on right hand Z plate?

If not your earth (red) wire is at fault

Pull blue /brown wire off Zenner Diode connect between this and Z plate If bulb does not light check fuse If fuse ok then check ends of wire at battery in case it has been crimped onto insulation

If above ok move onto ignition switch does bulb light with one lead on terminal with Blue /brown wire and other on z plate ?

put key in and turn 1 position clockwise and check output to coil white if I remember correctly

now turn switch to position 2 and check you have output to lights

Good luck, Let us all know how you get on.

NB beware of using conditioner chargers to supply a voltage, many give no output when simply joined to a loom or a completely flat battery. If you suspect battery get some jump leads to a car or go to car boot and invest in traditional charger one with Davenset on it should last a lifetime if you change the output leads and croc clips every 10 or so years!

When you say

"No4 Position Ign + Lights = 000v

No3 Position Ign only = .630v

No 2 off= 13.06

No1 Parking lights= 000v"

is that when you turn the key to the appropriate position? ie when the ignition is switched on are you only getting .63V at the output?

I would disconnect the powerbox temporarily while you check out the continuity. From what I see that is only a charging regulator and has nothing to do with the ignition system.

Dear malcolm,

Perhaps I should have defined "Test progressively" as once you find bulb does not light you have to find out why

So you have a good earth but no power in blue /brown wire

go back to fuse holder remove fuse and test with bulb leads on earh and battery side of fuse holder does it light? If not you have faulty lead from battery to fuse holder

If it lights replace fuse and test with bulb on end of fuse furthest from battery again should light if fuse is good.

If OK so far find Blue/brown connections to capacitor and test between them and earth on z plate If you have no capacitor you may need to bridge these if both are not live,

again let me know how you get on

regards martin

Previously malcolm_patterson wrote:

Previously Martin Freeman wrote:

Dear Malcolm.

Test the old fashoned way using an indicator bulb in a bulb holder with 2 flying leads a couple of feet long. Check it works on a car battery before you start. then test progressively;

Does it light across battery? if not battery at fault

Does it light with one lead on negative battery and one lead on right hand Z plate?

If not your earth (red) wire is at fault

Pull blue /brown wire off Zenner Diode connect between this and Z plate If bulb does not light check fuse If fuse ok then check ends of wire at battery in case it has been crimped onto insulation

If above ok move onto ignition switch does bulb light with one lead on terminal with Blue /brown wire and other on z plate ?

put key in and turn 1 position clockwise and check output to coil white if I remember correctly

now turn switch to position 2 and check you have output to lights

Good luck, Let us all know how you get on.

NB beware of using conditioner chargers to supply a voltage, many give no output when simply joined to a loom or a completely flat battery. If you suspect battery get some jump leads to a car or go to car boot and invest in traditional charger one with Davenset on it should last a lifetime if you change the output leads and croc clips every 10 or so years!

Hi Martin

Rigged a bulb up and here's my results

Good light across battery

Good light negative pole on battery and Z plate.

No light on Zener feed wire but fit wire back and beep test worked

Fuse OK

Wires OK

On ignition switch No light between BR & BL wire and Z plate

Position 2 no output from bulb or meter

Any idea how I check the Boyer Bransden powerbox PBOX00108

Thank You

Malcolm

Several bits of poor information here. There is NOT a zener if you have a Boyer Power box. Zeners go with rectifiers. Boyer Power Boxes are regulator/rectifiers hence no Zener. The symptons (bad spelling due to bad spellchecker on this site STILL not fixed) of this problem is 'nothing working' ie lost power from battery. Again nothing to do with Boyer Power Box. in fact nothing to do with ignition either. The battery feeds the lighting system so the lights system is the first to get working, then ignition, then worry about battery charging via the BB Power Box.

My AN supplied harness also had a dodgy fuse holder, worked for a week or so, replaced with modern fuse holder and 15 amp regrettable fuse.

Previously john_holmes wrote:

My AN supplied harness also had a dodgy fuse holder, worked for a week or so, replaced with modern fuse holder and 15 amp regrettable fuse.

Hi John,

Be very careful with resettable fuses. Check the spec. Some fuses that will take 15A will not blow until 28A and then could take up to 30 seconds. This could then become regrettable.

It is much better to use a normal fuse and carry spares. I use the automotive blade type which never come loose.

Tony

Previously malcolm_patterson wrote:

Hi Alan. Martin and Ian

Well I've moved on successfully after all your very useful suggestions.

In the end it had to be either Battery or Fuse Holder that foxed me for weeks.

Thanks to Busters who load tested my Motobatt battery and satisfied me that it was functioning fine. As for the fuse holder, in desperationafter checking withMultimeter and headlamp bulb testI bought a replacement unit, well have a guess what it worked so AN please check your fuse holder stock as mine had an insidediameter at one end that didn't allow the fuse to touch the brass nipple that's spring loaded. I've now fitted a car fuse type no problem.

Thanks everybody now to setting up the singleMK11 Amal 34 mm carb????

That's very good that you are sorted. I would very much like to see (Or at least a picture) of this offensive fuse holder. There are several types on the market and as I sell one type I want to know I do not see the wrong type. By the way although the glass tube type fuse holders have a spring in them it must NOT carry the electricity. You might have to examine the fuse holder closely to decide if this is the case but it is essential, or the spring losses its tension if it carries electricity and a fire or failure awaits you.

Do I remember correctly that some fuses were rated at half the value at which they would blow? Slow blow? Glass ones? Or has my memory finally gone the same way as so many other bits of me?

Previously ian_soady wrote:

Do I remember correctly that some fuses were rated at half the value at which they would blow? Slow blow? Glass ones? Or has my memory finally gone the same way as so many other bits of me?

FUSES! Having in a former life been a HI Fi Engineer I had quite a collection of fuses, (this is glass tube type) there were 1 1/4, 1, 5/8 and several more, then there were values from a few milliamps to many amps, then there was fast blow, semi-fast blow, slow blow, surge delayed in each size-we have boxes of the d**** things.

The original Lucas ones were often rated 17A carrying 35A blow, what happens at 25A we should not ask about eh George?

Previously Alan Osborn wrote:

Previously ian_soady wrote:

Do I remember correctly that some fuses were rated at half the value at which they would blow? Slow blow? Glass ones? Or has my memory finally gone the same way as so many other bits of me?

FUSES! Having in a former life been a HI Fi Engineer I had quite a collection of fuses, (this is glass tube type) there were 1 1/4, 1, 5/8 and several more, then there were values from a few milliamps to many amps, then there was fast blow, semi-fast blow, slow blow, surge delayed in each size-we have boxes of the d**** things.

The original Lucas ones were often rated 17A carrying 35A blow, what happens at 25A we should not ask about eh George?

YourrightAlan; Dependand on theconstruction and "filling" (silica, sand, glass etc.) ofthecartridge fuse, . The varying percentageofdelay wasidentifiedby F (Fast) or FF(veryfast)acting andsometimeasnail symbolto showtheywere slowacting. So, Alan, its true,youare still "on thebutton"

Cheers

Jon

My resettable fuse tests as 15a and works instantly when I induce a short.

Previously john_holmes wrote:

My resettable fuse tests as 15a and works instantly when I induce a short.

Hi John,

Can you give a part number / supplier please?

Thanks

Tony

Bought many years ago so can't remember supplier, will check for a part number.

Marked 28VDC on one side, iATY Taiwan the other. Google reveals nothing other than pork exports from Italy to Taiwan.