This is a read-only archive of the old Madabout Kitcars forum. New posts and replies are no longer possible, but every thread is still here to browse and read.
I think I'm missing the relay for the main lights but it would make sense if the outlet supply from that relay was only live with the ignition on.
I can't see there'd be any advantage in that. I find it handy to be able to use the headlights anytime when parked. It would also mean you couldn't use parking lights as the feed to the light switch supplies both. You could, of course, have separate switches for side and head lights...
I always fit one of those red key isolator switches into the heavy +ve battery to starter solenoid 135A (or more) feed, removing it when I leave the car, even if I'm only popping into a shop. Paranoid, moi?
I think I expected the headlights to automatically switch off with the ignition off so you don't flatten the battery if you accidentally leave them on.
Modern cars tend to have a buzzer that's activated when you open the driver's door when the lights are on, but I seem to recall that in most of my cars back in the 70's and 80's only the sidelights worked with the ignition off, but I could be wrong as it's a long time ago now.
As for security, I had a transponder immobiliser in my Spyder - you had to hold a 1p sized key fob close to a hidden loop to activate the ignition - and I'll be using something similar in my Speedster.
Anyway, I'll be spending this afternoon with a test meter trying to trace which wire does what in my loom as there are coloured wires that just don't match anything in the Haynes manual wiring diagram. Once I've worked that out I'll be close to getting the engine started for the first time.
I hope that goes better than the first firing of the straight six in my Spyder.
On first turn of the key the starter solenoid exploded sending a shower of sparks into the fuel cascading out of the carburettors.
Bit of a non-sequitur, but this took me back to the day in the 50s when my mother and I were exploring the first self-service Woolworth in London. Goods that you could pick up and examine without asking a flunky - revolutionary! Anyway, I remember amongst the accessories available to enhance your pride and joy were indicators and heaters...
I'm really keen to have all the electrics fully sorted before my first attempt at starting the engine as I have fitted a reground cam. The instructions for the cam say to run the engine for 20 mins at 2,000rpm on first start without lots of slow cranking beforehand, as this will fuse the bearing surfaces of the cam and followers together, scrapping both, so it's important the engine fires quickly.
Now, the wiring diagram and colours/combination of actual wires in my loom indicate I have a built in ballast resistor wire on the ignition circuit, so I need a 1.5 ohm ballast coil rather than a standard 3 ohm coil.
As luck would have it, my Midget runs a separate ballast resistor on the ignition circuit and I have a spare ballast coil in the boot, hurrah!
For those unfamiliar with such wizardry, the ballast resistor or wire reduces the voltage from 12v down to 6v, which powers the 6v ballast coil in normal running.
The ballast resistor or wire is then overridden by another wire carrying 12v directly from the output side of the starter solenoid on engine start to make sure there's still a strong spark when the starter motor is pulling all the current out of the battery. The coil won't fail during start up because it doesn't have long enough to overheat while it's being 'overpowered'.
With this in mind I connected the battery and checked the voltage at the coil positive terminal, which should be 6v. Hmm, 12 volts present.
I checked the resistance from the ignition switch to the coil positive terminal and it's 2 ohms. The manual says 1.5 ohms, which is supposed to drop the voltage to around 6, but I have 12. I also checked the resistance through the secondary coil positive circuit from the starter solenoid and that's virtually zero ohms, which is right.
I then checked the voltage at the Midget's positive coil terminal and it's 8 volts as it should be.
As if that wasn't confusing enough, I then checked the resistance across the coil that's happily running in the Midget, the new spare coil, the coil that was in the Midget when the electronic ignition module failed and a new Lucas DLB105 Sports coil I have on the shelf, and they're all the same at 3.5 ohms.
After much head scratching (electrics are a bit of a mystery to me) I decided to run a zero resistance 12v to the coil positive terminal, use the Lucas sports coil which is the only one I know for sure isn't a ballast coil and ditch the ballast wire.
Everything seems to be fine now, I have 12v where I expect it and the right coil fitted to handle it. Hopefully...
I'm waiting on a few parts for the cooling system at the moment and once they arrive there's nothing to stop me firing up the engine. I do hope it all works.
The circuit for the 'cranking voltage to the coil' may only happen when the starter is cranking, and is connected when the plate in the solenoid is pulled into position onto the 2 large connectors - via another connector at the same time (I hope that makes sense). The clue is if you have 2 smaller wires connected to 2 posts on the solenoid c/f 1.
Thanks Mitchelkitman, you're absolutely right, that is how it works. The problem I had was that the voltage was too high at 12v in the 'normally live' coil circuit at the end of the ballast wire, where it's supposed to be 6v or thereabouts.
I have a separate ballast resistor in series with the 'normally live' ignition wire in my Midget and the coil positive wire reads 8v until you crank it, then it jumps to 12v, as you say, from a connection on the output side of the starter solenoid.
I did a bit of research about the ballast wire in old Triumphs and it seems the resistance breaks down over time leaving you with burnt out points and a fried coil, hence bypassing it in mine as I suspect it's failed.
The whole ballast resistor thing was a good idea fifty years ago, but with a well maintained ignition system and electronic ignition starting shouldn't be a problem, fingers crossed...
Aye these old cars are objects of mystery and education at times. When I met her my (now) Wife had an ageing Volvo 340 (manual 'box thankfully). This car was still a nightmare. One day (I was convalessing from operations) it packed up on her way to work. Long story short, points burnt out, garage replaced, 2 weeks later same. It was only when I got a 'jolt' off the points when flicking them that the mystery was solved - coil was also sending HT through the LT circuit! The car had a novel design of seat (2 door car) which were hinged so they tilted forward and towards the trans tunnel.
You only get a voltage drop across a resistor when there is a current flowing so if the points were open (or dirty?) you'll get the full 12 volts.
Hmm, electrics really aren't my thing and I'm really confused now.
Wouldn't the current flowing through the test meter complete the circuit and drop the voltage? And why does the positive terminal of my Midget's coil have 8v after the ballast resistor from a battery showing 12.6v when I'm connecting the same test meter to it?
I need to read up on low voltage electrics, methinks...
Oh, and I have now managed to check that I do have a spark and I've set the advance with a strobe by turning the engine over on the starter for a few seconds at a time (any longer might damage the new cam). I should be able to start the engine for the first time later this week once some cooling system parts have arrived from Canleys, which are essential as the motor has to run at 2,000rpm for twenty minutes immediately on start up to bed in the new camshaft.
I'm so glad I decided to run a (nominally) zero resistance wire to my coil and give it 12 volts under all conditions.
The reason I've got myself in a tizzy about this is that when my midget developed a misfire I noticed that the coil was getting red hot, so replaced it with a non-ballast 12v one as I didn't realise I had a ballast resistor in the circuit.
First run out after fitting it the misfire had gone and the car ran fine suggesting the old coil was on the way out, but at the end of a 30 mile trip to the coast the engine conked out as I pulled on to my driveway and wouldn't restart.
After a bit of investigation I replaced the coil with a ballast coil but still no spark, then I took out the fancy electronic ignition module and put the points back in and it ran. A bit of research revealed that the electronic ignition module probably failed because of the wrong voltage going to it.
By then I had already committed to electronic ignition on my Speedster's engine and I don't want to burn it out by under or overpowering it. At least now I know that it's connected in accordance with the manufacturer's instructions so it shouldn't fail.
Progress has been a bit slow for a couple of reasons: First off, engine issues, more specifically trying to get a leak free cooling system. I've had two cracked water pump housings and the third one I tried had stripped threads on both bolt holes for the thermostat cover. That's all sorted now and I'm hoping to fire the engine this weekend.
Second reason is that it's now the season for my other hobby, grubbing around in muddy fields looking for 'treasure'.
I'd like to say 'There's gold in them there hills' but I live in Norfolk. Gold, there is, nonetheless -
Et Voila, one Ambiani Gallic wars gold stater, struck in about 57BC by a tribe in Gaul (Northern France) to pay an army of Celtic warriors to fight against the invading Roman army led by one Julius Caeser.
Norfolk has the largest number of 'treasure' items recorded under the 1996 Treasure Act in the UK. Its history is one of the reasons I settled here from my native Essex back in the early 90's.
What I'll do now is record this find with the local archaeological unit then have it properly valued. I have a 50:50 agreement with the landowner for any valuable items I find and this certainly qualifies.
Once we know what it's worth I'll hopefully be able to afford to buy out his half so I can keep it as it's all about the connection with history for me rather than the value.
After all, the last person to touch this before me was almost certainly an Iceni warrior who fought in battles against Julius Caesar. You can't really put a price on that!
Wow - fantastic find. Doing an online search (which you've probably already done) suggests about £500 - £1000, but as you say it's the history that's important. It irritates me how the TV programmes (and indeed classic car magazines) highlight the 'value' in ££s as the main objective - In fact if I see the classic car mags with covers saying 'what's the best investment car to buy?' or similar, I deliberately avoid them. Hope you will be able to keep your coin!
I also enjoy Aussie Gold Hunters - a good 'escape from reality' viewing experience. Apparently, the best way to get gold these days is via scrap electrical equipment!
Electrical equipment gold recovery is too messy. Nitric acid needed gives off too many toxic fumes that will make you puke !
The local car boot yields some nice little nuggits from time to time !
Well done on your find Mr Towed!
Thanks for the kind words, guys. It is a spectacular find and in pretty much as minted condition once I rinsed the mud off it.
Given that, I'd estimate it to be at the high end of the value range for one of these, so around £1,000 to £1,200
Luckily I can afford to pay my half of that so I should be able to hang on to it, but if the valuation is much more then my (wealthy although he'd never admit it despite the pristine E Type roadster/other classics/new Velar etc.) farmer friend might have to buy out my share.
He's also really interested in the history of his land and I often hand over small items that have a connection to the land he owns as he loves them just as much as I do.
These have included a lovely 14th Century bronze seal matrix used for impressing the owner's personal coat of arms in molten wax to seal documents, and most recently, an enamel badge from the National Agricultural Labourers and Rural Workers Union, which was an early 20th Century land workers' rights movement.
It's a great hobby which gets me out in the fresh air, but it does eat into the time I have for car building. It won't be long until all the land I have permission to search is under crops, though, so I'll be back in the garage soon.
Sounds good Gary, are you going weather-beaten patina paint and faded numbers?
I'm afraid not ... I'm doing shiney paint etc but with an outlaw attitude towards stance etc.
Customer has some definite ideas and comes from a VW / Porsche background
