Indicator Switch - current 'leakage'?

[MoreWellie]

The other option would be to use the original switch to drive a couple of small relays that would pull enough current to hide the issue

This should work providing you have somewhere to hide the relays

 

[MoreWellie]

Before you get too hung up on dismantling the column and switch. If you have room to hide relays I would look at this route first

It is almost certainly not frayed wires as this would be more likely to cause a short rather than a "bleed"

 

[Erie Fred]

I'm going out to the garage. I may be some time.

I'll report back - eventually.

Can some one please tie a rope around him for retrieval ?

 

[500e]

The wire usually frays/rots at the egress from the tube and is covered in oil & No I am not Volunteering did stupid things on cars for to long but nice try
Not all had the 3 grub screws either, only have a vague recollection.
Thought the lower clamp ones did not have grub screws as the horn and indicator switch stayed still, and it was sort of held on the center tube
Had a TD21 a real gents carriage, then went to Bristol's 410/411/ 412 rusted a bit alloy and steel but cheap motors & gear boxes being American Chrysler V8s

 

[rtcosic]

The wire usually frays/rots at the egress from the tube and is covered in oil & No I am not Volunteering did stupid things on cars for to long but nice try
Not all had the 3 grub screws either, only have a vague recollection.
Thought the lower clamp ones did not have grub screws as the horn and indicator switch stayed still, and it was sort of held on the center tube
Had a TD21 a real gents carriage, then went to Bristol's 410/411/ 412 rusted a bit alloy and steel but cheap motors & gear boxes being American Chrysler V8s

Definitely has the grub screws. I saw those and removed them and tentatively pried the switch with my fingernails to no avail.
The wire exiting the steering box has a suspicious amount of insulating tape on it, but I left it alone lest it disintegrated before I knew how to replace it. I took the oil covering as entirely normal on a 70 year old lady.

I'm running errands this afternoon and haven't explored further.

Ah, Bristols. Do tell is it true that they only come in pairs?

Phnnarr, phnarr, nudge, nudge, wink, wink, know what I mean sir?

 

[500e]

We looked after a few

 

[500e]

Revington TR for idea

 

[daedalusminos]

When you say solid state do you mean no relays? Is the vehicle positive earth?

 

[rtcosic]

Late afternoon grovelling session:

Oily starting point:

10 minutes of degreasing later I can see what I need to do:

remove the suspicious tape and surprise, surprise:

Nice clean easy job:

Glad I have the Tickford drophead and not the Mulliner saloon - the tube is VERY long. 70 year's of accumulated unpleasantness:

Not entirely sure what I'm looking at yet, but shower and SWMBO to dinner calls. Tomorrow is another day:

There might even have once been a self-cancelling feature?

@500e Thanks for that it will be useful.

One of the first tasks was to switch the car to negative earth whilst everything was still analogue.

 

[rtcosic]

For @500e this appeared in the Alvis Group on Facebook today.

Especially for you an Alvis with an American V8:

Background notes
Jim Burns was a businessman who had made his fortune in the world of pop music manufacturing electric guitars for the likes of The Shadows and Eric Clapton, he was also a genuine petrol head and a keen Alvis enthusiast, so having sold his interests in his business he decided to try his luck in the automotive industry. Rumour has it that Burns was in an Alvis dealership about to order his new car when he overheard a Texan millionaire being told by a salesman that Alvis cars were not for export. Burns thought he had spotted a niche in the market for an ‘export-only’ Alvis but it had to be faster and better looking. Despite being warned off such a project, Burns set about the task of creating his own interpretation of the only V8 Alvis in the world. Burns had every confidence that, once Alvis had seen his prototype, they would agree to go into some kind of low-volume manufacturing agreement. His plan was simple, make the 3 Litre Alvis TD21 faster, more attractive and move it up market, and of course more exportable to the American market. Burns’ concept of this special Alvis involved using a TD21, possibly his own car, and to then take it through various stages of modification. First, the ageing straight-six 115bhp engine was replaced with a whopping Chevrolet Corvette unit producing 300 bhp. This 5,356cc unit would give the car a power increase of some 240 per cent with no weight penalty whatsoever. Then to set about considerably modifying the bodywork by lowering the roof line by several inches. This streamlining was intended as a facelift without incurring the cost of totally replacing the body.
Work began in the autumn of 1966, Burns ordered a new chassis and suspension from Alvis and entrusted the mechanical development to Jim Keeble of Keewest Developments, the firm Keeble had formed with Geoffrey West after the demise of Gordon Keeble. The chassis only required fairly minimal alterations, mainly to the cross member, in order to accommodate the V8 engine and the gearbox rear support. The body shell was then replaced on the modified chassis and taken to Williams and Pritchard Ltd, a North London coachbuilder, who specialised in building one-off body shells. The roof was lowered which meant cutting down the pillars and door frames. This reduced the size of the side glass whilst retaining the original windscreen but with a steeper rake. Both the front and rear wings were then replaced with aluminium items which were elongated along with horizontally paired headlights and slim line wraparound bumpers. The final phase of the project involved the car being sent to Wood & Pickett Ltd for detailed re-trimming in white hide with blue piping along with a complete new fascia design using an impressive bank of gauges and switch gear sourced from the Gordon Keeble factory.
This was the period of various ‘motor mergers’ in the Midlands. First Rover allied with Alvis, then in March of 1967 Rover itself was swallowed by Leyland. Leyland were not in the least interested in a low volume bespoke motor car of any description and since the last Alvis car had left the factory in August of 1967, any move to revive it was utterly doomed. Alvis management did, it is understood, see the car and drive it when a Wood and Pickett director drove the car up to the Alvis factory in Coventry. The month was October, the reception polite, but with tooling suspended there was no way forward. There were no orders and no production facilities either. The ending was even sadder as Wood and Pickett Ltd, being the only participants in the project who had not been paid, took possession of the vehicle and eventually sold it to Guy Salmon Ltd in 1968. Built at a cost in excess of £10,000, this V8 Alvis would have been sold at around £6000 had production got underway. Compare this to the retail price of a 1967 Jensen Interceptor of £3,743 it could hardly have been considered cheap. If it had made it to production two years earlier and without the ‘‘merger factor” it could well have found itself a niche in the market place. Such is the execution of the concept, the car has survived to this day with enthusiastic care and attention to keep alive the only 5.4-litre Alvis in existence.
According to documented records, RYX 997F was advertised by dealers Guy Salmon in 1968 in Autocar magazine for £3,950 but was subsequently sold for less in May of 1969 to a Somerset farmer with fewer than 1,000 miles on the clock. The Burns Special was later sold to an enthusiast in the North of England where it remained for the next ten years. It was then purchased by a reclusive collector called Michael Wrest. The vehicle then passed into the hands of another enthusiast in Wigan before appearing in the auction at the 1983 Northern Classic Car Show held at Bellevue in Manchester. It was spotted at the event by a Mr Holt and his mother; apparently she wanted the car on the spot purely because of its sumptuous white leather interior. Stockport florist Holt already owned an Alvis TA14 Tickford at the time and subsequently looked after the car and inherited it when his mother passed away.

 

[jsf55]

Thats the stuff of nightmares !

 

[500e]

Good clean to start then strip V carefully wire looks good so it should not be a problem further up, looks like you have plenty of loose at the bottom of tube the wires wont go up without cutting the bullets off.
I have some outer protection for free(not cotton though) let me know tube ID and OD and length will put in some shrink sleeve for end of tube ETC + PM address .
I expect someone here has bullets to re solder or crimp , I expect you know there are 2 different bullets the crimp one has a distinct waist, There was a tool for crimping them, gave mine away, cutters not good point contact = stress riser the tool crimped about 3/32 flat profile

 

[rtcosic]

Retested the switch with the entire assembly on the bench, all 1.8 metres of inner column. I got exactly the same readings as when it was in the car so the issue is isolated to the switch and associated internal column wiring.

Fiddly little screws accessible via holes once the various components are lined up. Fiddly, but fairly obvious and straightforward. Horn push wiper:

Internal wiring connections to the back of the switch before and after degreasing. The whole assembly was thick with grease with an odd texture - almost like CV grease. I wonder if it is slightly conductive?

Cleaned:

Note the blobs of solder on the brass nuts. 3 handed job to desolder, hold nut and turn screw from the other side, but eventually reduced to the component parts shown in the TR drawing kindly provided by @500e above:

Of course in any assembly containing multiple small components and springs no matter how careful you are that ominous 'sprong' sound is never far away.

Did you notice the little roller thing?

Part of the 'latching' element of the switch:



Of course, it went 'sprong'. The spring and brass components were nestling conveniently by my right foot. The little roller? I could see the brass widget housed another component but it had all been hidden behind the switch lever so I didn't know what it looked like. Cue 20 minutes of careful sweeping of the floor, removal of storage boxes, emptying them, more sweeping, passing of magnets, filtering of dust through fingers and it eventually surfaced from the floor in the farthest corner under the bottom shelf of the workbench. Phew!

As well as the caked-on grease, a screw holding the external lever of the switch was loose which may have contributed to the symptom. But the other 'smoking gun' is the damage (arcing?) in the area around the right indicator connection:

Just to confuse anyone who hasn't clicked away already it's actually on the left in these photographs:

At this point - nearly 3 hours after I started - I decided discretion was the better part of valour, take the win of finding all three little beasties and retired for a beer on the terrace. Tomorrow I'll clear up the workbench, lay down some clean white paper and start the reassembly of the now clean components.

I'll sacrifice a passing child to the Small God of 'sprong' capable elements first though.

 

[Cobbler]

Nice to see the photos of the Alvis, my old boss back in the late ‘60s had one. A TD21 I think, from what I recall one with twin vertical headlights. He previously worked for DeHavilland & I understood it was his company car, when he retired from there he kept the car. It only came out high days & holidays, his usual transport was a Rover 2000TC. No idea what happened to it when he died.

 

[Erie Fred]

Looks like the rope held, and you made it back out alive....good looking work too.

 

[badabec]

Regarding odd switch behaviour, my Citroen DS would light up the 'big red light of doom' due to low hydraulic pressure. The switch used a Bowden tube to open and close the contacts. On the bench, even with the contacts held open with a piece of plastic, there was still continuity and a test lamp would light up.
I fixed it by warming the switch with a hot air gun. The heat must have driven out the moisture from the body of the switch and normal service was resumed.

 

[rtcosic]

Argh! A slight disaster! The brass wiper that makes the circuit between the central power plate and the two indicator circuit pins was very badly worn on the edges where it contacts the pins. The wear in the pins was a good clue to just how worn it was.

I thought it a good idea to fill in the worn areas with solder, but it turns out the wear is so great one leg 'came off in my hand Guv':

I only have plumbing or electrical type solder which obviously doesn't have the mechanical strength to repair this.
I don't have silver solder/brazing equipment or supplies.
I don't have the skills to cut a replacement from brass sheet - which I don't have anyway.

Any ideas?

 

[Blobber]

I dont think you need a great deal of skill to cut one of those out of some brass sheet, junior hacksaw and some files? I Had a little box about with various bits of brass sheet somewhere, Ill try and find it

 

[rtcosic]

Quite right - I think I had a bit of 'target fixation' there.
I'll look to buy a little coping saw from ScrewStation and practice on a bean tin.

 

[rtcosic]

I don't feel like such a berk after all. There used to be a repair kit for these switches including a new wiper, so they must have been expected to wear out: