Returned from Woodcote steam rally without having to tighten up wheels or retrieve snapped wheel studs charging light came on about 15 miles from Everton on the way there... ammeter hovering at 0 and no increase when revved so I did the right thing, checked the fanbelt and put it on winter charge (no difference) and pressed on to the steam fair in the hope that once cool it would work again! It didn't but the stater still spins ok after about 140 miles so it must be putting out enough to cover the coil and fuel pump? Before I left for the trip home I checked the brushes, the one with a bare rope type wire on it (1st or 3rd) had come off and I was pleased to have found the fault but refitting it made no difference! checked the fuse in the box mounted on the side of it and replaced the (domestic 13a!) fuse in the fuse/cut out box. I have a new dynamo but without the box on it so don't know which wires go where if I swap the box over, also don't know how to test output on these sv dynamos. Any pointers appreciated...
Secondly, years ago the front brakes would occasionally "graunch" and since getting the car back it has done over 600 miles silently. It started the noise in the isle of wight and has got progressively worse to the point where the brakes were more of a barrier to getting home today than the charging It's no good being forceful as it throws your foot off the pedal and feels like wobbly shoes-anyone come accross this before? It's the cable brakes with aluminium backplates which I don't think are standard...
Not good on electrics, but having read the tech topic in the members area my understanding is that dynamos with the box of coils have the box controling the winter or summer charge and the ones without this ie my sparte and the 8 dynamo on the saloon have a resistance wire inside doing the job of the external box. All have 3 brushes, the 3rd providing the winter boost? So need to check output by joining the 2 output cables and using a meter at tickover... The bizarre thing is that the battery only took about 1/2 hour to top up with a battery charger so maybe I could have used lights and wiper during my 3 hour evening drive through the torrential rain on country lanes!
The third brush controls the output, and the resistors (together with a switch) control winter/summer output. So both do the same sort of thing, its is just that the current produced is doubled when you switch to winter setting. The adjustable third brush allows you to set the amount of juice going to the battery under normal load. Not a very good explanation, but I hope you see what I mean.
But you are right about the location of the half charge resistor - it is either on the box on the dynamo (some SV dynamos) or inside the dynamo (all OHC).
In the box I already have a wire connecting the terminals in situ, looking at the 4 seater it's the same. Have carried out the test in the tech section (once I found it!) and with another wire connecting the terminals the voltage goes 0, 10, 14, 18, 14, 10, 0 back and forth up and down so I assume I havew a charge and assume (as both dynamos have a wire but differing types of wire) it was a popular thing to connect the 2 resistors thus bypassing the summer/winter affair? Will reconnect and see if points close on regulator, thought these were indestructible, can I replace it with a couple of quids worth of wizardry?
Sorry but i disagree, one of the bikes has a magneto and I've found that easier to cope with-flat battery and it still runs with no fear of whether you've enough power to get you home in daylight (i once rode it a couple of miles on the pavement when dynamo failed at night but i don't think you're technically allowed to do that ) when it has no spark then it's the magneto. I was actually bemoaning the lack of magneto to ensure I'd make it home yesterday, maybe I need a magneto conversion with acetylene lighting?
Re your brakes, sounds like the linings might be snatching somehow. Can you tell if it is one wheel or all of them? Is it pulling one way or the other? You could slack off one cable at a time to find out, or just whip the drums off and see what's going on.
How it was in the 50s - All of my old cars in the 50s, 60s and 70s had mags, I loved them, they NEVER went wrong. In 1957 I purchased a 1927, 9.20hp Humber Saloon. This was my everyday day and was used all the time. It has a mag and a dymo starter. The dynamo never worked aand I took a charger to worka and charged the battery every day, especially in the winter. I did this for 5 years!! Highlander.
Havn't looked in brakes yet but it has always affected the front (it did this when dad had it but not as bad and After a few hundred miles i assumed the previous owner had sorted this out!) hard to say which side or both. Just thought that if all looked ok in there i would need some pointers!
Have found a spare cf3 cut out and tried that but with no joy, following test procedure of closing points at tickover, raising engine speed and releasing points they spring open on both cutouts, I assume this means both are broken. The ignition light goes out when points are closed but ammeter still shows no charge which Suggests no charging!? I have a spare rebuilt dynamo that only has a D & F terminal with no windings, if I identify the D & F terminals in the other dynamo with resistance box on it can I swap it over? At least I'd be sure of the dynamo then not being the problem!?
I think the article describes a fairly simple method of how to test the dynamo in isolation - by shorting the two output wires together? I think the first thing to do is determine whether the dynamo is sound or not, and only then start working you nway through to the cut-out.
Have done this but suspiciously the wires are already linked using a piece of bare copper household wire, the one on the 4 seater that i checked for reference has also got them linked but with a bit of ancient autocable. My readout for the test was oscilating from 0-18 volts rather than a steady reading!
By the way, stripped brakes, last owner appears to have fitted new shoes (probably to try and cure problem) so assume the new shoes were a sort term cure until they wore which then showed up the wobbly actuating cam. Being aluminium plates the post has worn the hole to a wobbly fit! I'm assuming this is the problem otherwise I can see no problems! Changing backplates for the spares I was going to use on "the ox"! incidentally, these backplates are aluminium and I always assumed it was a '32 feature but have been told they're not minor. They fit perfectly and have not been altered, the minor drums fit and even the brake shoe posts are minor. Are they hornet or mg? Should they go with the finned aluminium drums incorrectly fitted on "the ox"? can't photo them as Lindas on hols with the camera!
Fascinating - never heard of ali drums on any of our cars before. Can you post some pics? I presume the brake cam (and fulcrum pin) are mounted in bronze bushes - not directly in the alloy?
charging light came on about 15 miles from Everton on the way there... ammeter hovering at 0 and no increase when revved so I did the right thing, checked the fanbelt and put it on winter charge (no difference) and pressed on to the steam fair in the hope that once cool it would work again! It didn't but the stater still spins ok after about 140 miles so it must be putting out enough to cover the coil and fuel pump? Before I left for the trip home I checked the brushes, the one with a bare rope type wire on it (1st or 3rd) had come off and I was pleased to have found the fault but refitting it made no difference! checked the fuse in the box mounted on the side of it and replaced the (domestic 13a!) fuse in the fuse/cut out box. I have a new dynamo but without the box on it so don't know which wires go where if I swap the box over, also don't know how to test output on these sv dynamos. Any pointers appreciated...
It's no good being forceful as it throws your foot off the pedal and feels like wobbly shoes-anyone come accross this before? It's the cable brakes with aluminium backplates which I don't think are standard...
incidentally, these backplates are aluminium and I always assumed it was a '32 feature but have been told they're not minor. They fit perfectly and have not been altered, the minor drums fit and even the brake shoe posts are minor. Are they hornet or mg? Should they go with the finned aluminium drums incorrectly fitted on "the ox"? can't photo them as Lindas on hols with the camera!