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Yes Wally you are pretty much there. So you have won yet another MO! It was the "Compacting Factor Test" devised by The Road Transport Research Laboratory & this particular illustration comes from Military Engineering Vol XIV - Concrete Part I, Practice, 1952. An explanation of it is best described here: http://www.engineeringcivil.com/workability-of-fresh-concrete-by-compacting-factor-test.html

Yes it is indeed Wally. Well done! Just need to know its purpose now.

Good thought Wally but not a food product & this does eventually become harder than bread.

To recap, this is not for use with liquids. But it is for solid matter that has a gooey consistency of varying density.

Richard I suppose "flavour" was not a very appropriate word to use in that context. What I was meaning to say was that I sympathised with Derek that it had a look of being that sort of thing, although in this instance it wasn't.

I don't know how you get you drinking water in Kent Richard, we don't even do that over here. So sorry to disappoint the latrine watching fraternity on here, but nothing to do with humane waste products. If it helps, this is 1952 & the apparatus evolved from another government body.

It does look like that sort of thing Wally, but isn't though.

Not necessarily radioactive Derek, it does have a certain lavatorial flavour but sorry to disappoint its not that sort of thing this time I'm afraid.

Good thinking but not a liquid going through.

Ah well I thought the gardeners out there might come up with something along those lines, but yes REME robust engineering & in the appropriate colours was something I hadn't considered. Pleasing to the CO no doubt, but this contrivance is not such a thing. Not really

That's excellent news, you must have an unimaginable glow of satisfaction that you could not have expected a week or so ago. I'm sure your appreciation of how charging systems work has come on by leaps & bound, so it really is worth persevering not only increasing your knowledge & experience but maintaining the historic & financial value of the vehicle. No it should be no hotter than any cable through which the current is flowing. It suggests: Dirty contacts on the silver plated pin connectors. The female pins have got expanded. There are some dry / failed joints in the soldered wires into the connector pins. They may show ok on a multimeter continuity test but unable to carry a heavy current. It is very unlikely that there are any defective joints to the generator plug inside the generator itself, more likely to be a cable problem as it can be subject to all sorts of trauma. Look at page 35.

Yes & yes

Err not really

Another Saturday night with no Dad's Army in this region So what is this all about?

No need to remove it. It is better to test it in situ because a stretched connection or broken wire might seem to recover once the cable is flaccid. Place one prod into the female of the connector (ie generator end), then rig up the other prod to a long wire & connect it to the male connector (ie generator panel end) of the wire under test, if necessary with a small crocodile clip. Also check there is no short-circuiting or even resistance leakage from U or V to earth or between U & V.

Yes but have you tested the continuity for each wire in the connecting harness supplying U & V from generator panel to generator? The cable is easily damaged internaly or stretched so that wire to pin connections become unreliable. You could temporarily hook up one of your new cables, & see what happens, but first test the U & V continuity in that.

You need to do a continuity test for each wire supplying U & V from generator panel to generator. See post #2

That's the bargain of the century! That sounds promising, just by energising the field winding & spinning by hand you can see if you get output to some degree. (In fact I have been doing the same to a Generator No.2 - this is a dynamo though with a gearbox & it cannot be spun but by more than half a revolution even that can produce some output) These readings are rather high & should really be 14.5 – 15.5 ohms. Take the average of at least three readings at different rotational points of the spindle. Also slowly rotate the spindle whilst measuring the resistance, if it jumps all over the place then the brushes are worn or there is grot, corrosion, pitting or grooving on the slip rings. High resistance or intermittent contact means a reduced magnetic field so less output, remember on a dynamo the field winding is on the outside but on an alternator the field winding is in the rotating bit (rotor) Not really unless you can get the resistance down by spinning them for a while to try & shift any grot. If you still get high readings, take the generator with the most consistent readings & remove the end cover & inspect the brushes & slip rings clean or replace as necessary. It is quite easy to access the end, see page 23.

Well Charles you've cornered the market on spares! Whatever the package cost you, the generator to generator panel cable is listed as £600, so I imagine you have done alright on the deal. This is important to establish that there is voltage coming through the cable from the generator panel to energise the field winding. The resistance measurement on the generator is equally important to establish there is continuity through the field winding & that the brushes are facilitating this. That's good news, I wonder how they did that without the generator panel & I hope they tested the output from the auxiliary diodes not just the main output diodes. You should be getting that irrespective of whether a generator panel is connected or not. There is no connection from shunt box to generator. It won't effect the ignition warning light. The generator Mk 2 & Mk 3 connections are identical, the outputs are the same except that the auxiliary diodes in the Mk 3 can deliver a higher current than those in a Mk 2. The warning light issue only occurs when using a different generator panel in an installation & shunt box designed for another panel.

Chris what was the outcome of your investigations? Did any advice on here help resolve the issue or are you still stuck with the problem?

Yes it doesn't seem a very sensible place to put it. Exposed all the wet muck from the ground & then it hampers access to do any testing or maintenance. Although in service I expect it was just pulled off & another fitted, then if it still didn't work the generator or cabling got changed. In the meantime I would do those tests for voltage (ign on & engine off) on the cable connector at the Generator at pins U & V. Then the resistance measurement (ign off) directly on the pins U & V on the Generator.

Page 91 of ACU lower diagram +ve lead to T4 -ve lead to Earth. If no reading disconnect connector on Generator. You need to test the field winding in the Generator & its supply. With ignition on you should get a reasonable voltage on pin U & V of the cable connector. If that is ok measure the resistance of pins U & V on the Generator. Should be appx 15 ohms but will fluctuate a bit if you rotate the pulley. If no reading most likely the carbon brushes need to be replaced. Alternatively there was an apparently working Generator on e bay for £20 yesterday.

Oh good, you will be alright then :-D

That is very strange because assuming the +ve supply your are feeding to the bulb is the same +ve supply that is going to the ignition switch then the bulb is getting 24v +ve at both ends of it when you switch the ignition on & irrespective of what the contact breaker is doing. Yes & the ignition is drawing 3A appx. Yes so definitely not charging. I think that was just a change in a seal. This very very important, the -ve rail from the Generator is not earthed. In earlier Gen Panels -ve was still floating above earth then earthed at the shunt box. However in the Gen Panel Mk 4 the -ve rail is connected to the case earth so it is absolutely crucial that the Gen Panel has a good earth. Whilst it is undergoing testing to reassure yourself that you have a good earth run a stout cable from the Gen Panel direct to the -ve terminal of the earthier battery. Your problem may be caused just by that! :-D

I don't know, none of mine are to hand. You need to watch out as I think it might be imperial with 72mm spacing between holes. In 1970 JSP 181 Part 1 laid down that all MOD technical publications would be in a loose-leaf format unless the sponsor could justify a bound publication. The paper sizes adopted were ISO ‘A’ sizes and punched to accommodate the new range of binders. Existing publications were to be re-punched to be fit the new binders with 80mm spacing. Some EMERs are pretty ragged being punched for the files with 23 pairs of clasps, then re-punched for 72mm spacing & then again for 80mm spacing. Just something to bear in mind in your pursuit of binders that all your documents are going to be compatible.