Has anyone rebuilt, or replaced the ignition contacts inside the Shadow switchbox?
My car will lose all power momentarily on the odd occasion, and when I lightly touch the ignition key all gauges and lights start working and the car re starts (hopefully without a backfire) This is worse when air cond is on and headlights etc etc. The higher the load the more it can happen.
Thanks to Jeff for the original link and Patrick for transcribing and translating it to a pdf file.
During a recent problem I had, I found that a previous owner had bypassed the starter motor relay and wired the starter solenoid direct to the switchbox. I reinstated the relay and so far have had no problems, but I do have a concern that the extra loading on the terminals in the switchbox will one day mean they will have to be replaced. This is a useful article, now downloaded to my archive.
This confirms my theory. No one makes things more complicated than they need to be better than Rolls Royce. OMG Nearly any car from the same date from any country has ignition switches up to 1/10 of the size.
Paul, below is a standard International/ Navistar 12v ignition switch that in some trucks using petrol or Diesel engines and using up to 4 120 amp batteries. They rarely fail, and if they do they cost about $60.
Are you able to explain why this switchbox resembles a massive amperage switch that looks like it could be used to switch on a power station?
Thanks for the awesome images Paul, you're a legend mate.
They were a slightly post war design, they last almost forever and I would put a small bet on you car having had a big bunch of keys on the key ring for a while.
They look so Rolls-Royce!
They've been using them since the 50's and I've probably only changed 10 sets of contacts. I've probably fitted more ignition switches or ignition switch parts than that on Seraphs and late Spirits . . . so I'm not that impressed with 'progress' :D
However . . .it would be nice just to plug in a new one for 60 Quid
They had a list of functions that needed fulfilling. No other set of switches would do what they wanted with the correct feel, look, and elegance.
I can not think of a car with a switch which does it's job with such authority and pride. It has a simple elegance and beauty that belies it's functions. Yours probably does about 10 different jobs.
It's been doing them for 50 years. . . . .and it will probably last another 50 quite merrily.
Perhaps we should all whip them out, put some electrical grease where necessary and pay homage to thir skills in over engineering.
Shame that they add 1mpg to the fuel consumption, weigh and cost the same as a small car, and tried to pop your skull when you got to sit on the middle of the bench seat or on the armrests in the front, between mummy and daddy, and se oik in a normal car halted your passage abruptly :D
This is such a useful thread. A previous owner of my car had bypassed the starter relay and was driving the starter solenoid direct from the switchbox. I've re-instated the relay but I was expecting trouble further down the line, due to the extra loading on the terminals. It's quite encouraging to read that these terminals are quite substantial and so may not have been damaged too much. It's also really useful to see all the pics and info on repairing the switchbox, should it eventually become necessary.
Mine can drive for weeks without an issue. Then it will cut out twice in 100 meters. But I almost never have to touch the key, it will just refire on its own. All gauges zero then fire back up, total loss of power. So my first inspection point was my isolation switch connections in the boot, battery terminals, then starter solenoid and the connection on my new reduction drive starter. All of these were ok.
My next job is to remove my fuse panel and re do ALL plug connections. (I had an issue with intermittent parkers and clearance lights which was rectified here)
But am sure that the switchbox will require doing.
TK Motors at Mossvale offers a rebuild service, where you mail the switchbox to Garrath, he will completely rebuild it and ship it back to you.
I would like to have a go at it myself, however Paul's images are quite daunting.
I would like to sit in on a rebuild as an apprentice first.
Patrick... While my recollection of such things is getting vague with time, do you recall the thread were the engine would cut out on left turns? I wonder if it may have some relevant information or things to check? Neither do I recall if that problem was ever resolved.
P.S. Is it just the engine, or entirely everything electrical...all lights, gauges, engine, etc as if the later, that would seem to be something basic regarading power from battery, grounds, etc, rather than strictly ignition related...but I am sure this already occured to you.
Christian, Thank you for reminding us of that thread, and you are right, I never saw the end result, thank you Geoff for supplying the link. It's good to see a thread that starts with a frustrated owner, that ends up with a smiling & happy owner.
Christian, Yes, my car loses everything, gauges drop dead, everything freezes in time. Then if I tap the key, they all spring back to life and the car will even refire if we have forward movement.
Have had a few good backfires as well. The last couple of times, I have not even had to tap the key, and it all comes back.
I did have this problem almost 12 months before the starter moter crapped it's pants, so the gear reduction starter was fitted. All electrical contacts as described before have all been double checked. Due to the fact I tap my key and things will right themselves, really indicates an issue in this area. I'm pretty confident with this.
I will just pull my fuse panel out and redo all plugs before I tackle the switchbox.
Patrick...I'm just thinking out loud and probably will say nothing you have not considered, but short of waiting for the phantom problem to manifest itself more consistently, it would add to your supposition that the fault is in the switchbox if instead of rectifying the problem by tapping the key, you could by manipulating the key, induce the problem. Were this to happen, it would indicate almost certainly that you have found the problem without first tearing it apart just to assess. Good luck there!
The reason I ask is if these lights go out also, then it's not the switchbox as the lights are not wired through it. They can be turned on with the ignition off. Difficult to monitor unless you do a lot of night driving. I was going to suggest driving on sidelights during the day so you could monitor the panel lights, but of course with your bright Australian sunlight I doubt you can even see the panel lights during the day.
I'd do plenty of diagnostics before stripping the switchbox. Although the switchbox is an obvious candidate, it could also be in the unfused circuitry before the switchbox. The obvious place to look is down by the starter motor as this is where the power lead feeds up to the switchbox/ammeter, however I note you have already cleaned that area when you fitted your new starter motor. One point of weakness in that area you might have missed is where the power lead goes through a bracket bolted to the side of the subframe. On my car the rubber grommet had perished and the insulation had worn through to the actual wire. It's worth unbolting and checking, just in case you are getting momentary shorts at this point. It's interesting that the similar fault on Christopher Williams Cloud was traced to this area.
The picture below shows the bracket and it can be seen by removing the right front wheel and peering through the gap.
Patrick... I think what Geoff is getting at is that (correct me if I err) the ignition key only turns off some of the electrics. Therefore if the power loss is total and complete including headlights and panel lights, the fault is likely elsewhere and the "touching of the key" may simply be coincidental.
There was another thread (hazy memory at work here) where the engine would not start (no power to the starter as I recall) and the fault ended up being a bad connection (fuseable link?) inside the main power line coming from the battery to the starter. If your power loss is total and absolute, much as if the battery cable were disconnected...then this may be worth checking.
P.S. I see that Geoff was writing at same time as I, and it perhaps was his thread that I recall. The point is the same...absolute power loss points to something else such as the main power feed. .
The thing is, Patrick's problem is intermittent and momentary, the worst kind of fault to trace. I like your idea of waggling the key during normal running to see if he can get the fault to occur. He could also try gently pulling at the wires around the starter motor to see if he can force the power loss that way. This is how Christopher Williams finally isolated the problem on his Cloud.
This problem needs to be solved as bump starting through an automatic gearbox can wreck it. I think the American term is push starting.
To show how elusive these wiring problems can be I have blown up the above picture and arrowed the part of the bare wire that was exposed and quite capable of leaking large amounts of current, particularly when wet. It's not obvious from a normal visual inspection.
As far as I am aware, there is no fuse on the main power lead from the battery to the starter motor and from the wire that runs from the starter motor to the fusebox. This is one of the reasons I always isolate my car when I put it in the garage.
I may be wrong on this. I am no expert however in all the years I have been reading this forum and other documentation I have never read about a fusible link on these cars. I have to assume the main power leads are not fused. I'd welcome being corrected on this if I have got it wrong.
Christian wrote in part . . . "Patrick, While my recollection of such things is getting vague with time, do you recall the thread were the engine would cut out on left turns? I wonder if it may have some relevant information or things to check? Neither do I recall if that problem was ever resolved."
This reminded me of a mechanic note included with Tootsie whereby when executing a u-turn the engine would quit - repeatedly. Checking the primary ignition connection to the engine revealed it would move during the turn as the engine shifted on the mounts and unscrewing it and cleaning with CorrosionX resolved the issue. Hope this helps.
From memory I am reasonably certain DRH14434 had a fusible link on the alternator output cable but I am not certain if there was one or a thermal overload reset switch on the main battery cable as well.
I cannot give any plausible reason for not including one on the battery cable.
Is it possible your car has a self-restoring thermal overload cut-out switch fitted?
If you have a fluctuating battery/alternator voltage for some reason, the reduction in voltage will increase the amperage draw and consequent heat generation to a level high enough to trigger the thermal switch which then resets shortly afterwards as the switch cools down giving the fault you describe.
I would fit it to the battery positive terminal to protect the entire system - this is the same reason for fitting an isolating switch to the negative battery terminal.
Others may have alternative ideas - in this case, I expect the most likely place would be somewhere in the engine bay at the end of the battery feed cable and before the connection to the starter solenoid.
After that, the only limit is your imagination.....
P.S. I think the headlights are fitted with thermal overload switches to protect the wiring system if someone installs high-power globes with high current draw. These can fail unexpectedly due to age or moisture penetration.
Wish I could remember that other thread but it was a "won't start" issue (i.e. no juice to starter) and poster had gone thru starter, relays, etc. As I recall, the work was being done by a shop and then by serendipity the mechanic stumbled upon a wrapped connection of some sort that had corroded and was stopping the electricity past that point. Ring any bells? What about grounds, such as (I think) referenced by J Beech? If the battery ground to chassis were having issues, would that cause an intermittant power failure? Of course that would be total and complete and not simply ignition?
P.S. Since Patrick reports that the issue occurs under heavy electrical load conditions, that may be a more relevant clue. Try running with headlights and fans on all the time in the process of trying to induce the problem and determine other correlations.
Granted but experience has taught me to never take anything for granted ....... this always comes back to haunt you when you least expect it .
DRH14434 suffered hard times in the UK after it was replaced by the original owner. The car also suffered the supreme indignity of father-in-law fitting a US "Continental" kit comprising a false spare wheel holder mounted on the boot after it arrived in Australia - removing this abomination after he died was the first work I did on the car and which was enthusiastically received when I took the car into York Motors shortly afterwards. Needless to say, they shared my opinion of the "upgrade" .
While we are on the topic of bad connections, I recommend an inspection of all the engine side of the toe-board connectors. If the car has ever lived in a corrosive environment this is an essential check, because if it isn't a problem now it will be soon.
When I first bought SBH10630 - in the "Oh heck, what have I done?" phase - I found one pin on the fixed "double-spade" part to be completely eaten away by green corrosion. It was permanently at 12 volts if I recall correctly. There was a spare pin in the unit, fortunately. "Vaseline" is a good treatment for these connections - lots of it. I've inspected them since while tracing other faults, and found no new problems.