Rob,
This is where the mystery continues.
The pull switch on the right operates a manual choke and was wired directly to the starter solenoid.
I have to say that, despite being a perfect match to the fog switch, this choke lead is highly likely to be an aftermarket fitting because the car, via junction box C5258 (discussed elsewhere), did of course have the original Otter.
On the other hand the sleeving on the fog lights wiring circuit did
Excellent, thanks much. The fog light installation with dashboard switch and sleeved wiring through a hole with grommet in the wing seems to be factory work, as best we can tell. We’d love to see a picture of the grommet and get an idea of the location of the holes.
Your other bracket label says spot light, so I wonder, could the other dashboard switch have originally been for the spot light (aka driving light)?
Agree that the use of the other dashboard switch as an otter switch bypass was done after it left the factory. I hadn’t heard of anyone rigging it up to the starter solenoid. I presume you mean the small wire terminal, in which case it would only work during starting, not to keep it running on cold days.
These brackets look to be home made most jaguar parts were stamped out and curvature on ends would be a curve these seem to be a series of flats?
Correction:
I meant carburettor solenoid
Terry,
See photo of JWK 651 (#660040) with a “rough” bracket. I wonder whether Jaguar really had a tool for this item as (I guess) less than 100 pieces have been made. In addition, the first brackets in 1950 had been made in the Competitions Department whereas later version (like those on Growlers car) had to be made in production and therefore could be a “copy” of the original bracket…
Also note the grommet for the fog lamp cable. The grommet mentioned in the SPC is C.976 and is far too large (1½ x ¾ “) for just 1 2 wire cable. I guess it’s either C.974 (1 x 5/16”) or C.975 (1¼ x ½ ”)
Bob K.
Here is a picture to show the position of the fog lamp holes.
I committed the schoolboy error of throwing away the severely degraded grommets which had been subjected to free radicals for 70 years!
However,
What is the diameter of the 2 holes through each bracket?
the car has gone to the paint shop, but when I visit next week I will measure the size of the holes and report back.
I posted these images a few years ago when the Fog Lamp - Spot Lamp subject was discussed. This is a Lucas advertisement from the early 1950s describing the four available lamps.
Both Growler’s XK120 and JWK651 (one of the 1950 Le Mans XK120s) were fitted with one Fog Lamp and one Spot Lamp. Each of these lamps takes a different type of bulb. Most bulbs sold today have a horizontal element, which is only designed to focus the fog lamps.
The Spot Lamps, also called Long Range Driving Lamps, take a special axial element bulb for correct focus.
I agree with Mike Balch. I also think that we have to distinguish between fog lamps SFT700 and long range lamps SLR700. According to the attached extract of a former Lucas Technical Service Document the fog lamp should be wired to the side lamp terminal of the lighting switch and the long range lamp to the mean beam terminal of the dipper switch. So I can imagine that cars that originally had two different lamps also had two switches one for the fog lamp and one for the long range lamp.
Kindest regards
Joerg
Mike,
Strangely enough the Long Range Lamp (or SLR in Lucas terms) never was a Jaguar “optional extra” (at least according the SPC). I’m curious whether Jaguar would replace one of the SFT lamps for a SLR.
Terry,
Below you can see what I decided might be the correct hole diameters. The (Fog or Spot) Lamp stem requires a hole with ⅝" ID and the Bumper bolts or the Extension for the Spring Bar are both ½" in diameter. Waiting for Growlers version.
The position of the cable hole beneath the lamps seems similar (identical?) to the ones on JWK 651: both a bit closer to the center of the car and (probably) just below the center of the lamps. The distance between the two might well be 16¾” ± ¼”.
Bob K.
I am going to guess that in fact they only ran the one wire up into foglight ie the power and provided earth back through mounting?
Spot on left seems to be a single wire?
Given the amount of research already done, and dare I say concluded on this subject, it is worth recapping a few salient points…
The XK120 SPC clearly identifies by Part Number and Description all the component parts of OPTIONAL single or dual FOG LAMP fitment, including wires involved and the length of the wires. It doesn’t advise/show routing of the wires, nor mounting location of the FOG LAMP switch, but length of wires for LHD and RHD installation, and provision of the rubber grommets and mounting clips gives a very strong clue as to the likely routing and mounting position of Fog Lamp switch and Fog Lamp(s). The only detail that was difficult to confirm was the exact dimensions of the two mounting brackets, with Robs drawings our collective best estimates, so I for one am delighted to see much CONFIRMATION of all this detail in GROWLERS photos and advice, and indeed I personally am satisfied that the Brackets and Fog Lamp aspects are as per a factory original installation.
BUT…
The factory only offered/listed a single or twin Fog Lamp installation, and not an single nor dual DRIVING LAMP installation with some very real and legally imposed differences that impact on a road-car installation. A race, rally or competition prepared XK120 can and did whatever was wanted, regardless of the road car legalities.
With these XK120 period Fog Lamps (SFT) and Driving Lamps (SLR) they all use a common body-shell and mounting pedestal, the only difference being in the interchangeable Lens or Light-Unit (and indeed the bulb). An SFT Fog Lamp has a carefully designed fluted glass lens to control the projected beam to suit driving in a Fog. A SLR Driving Lamp lens is plain/clear glass carefully designed to maximise the projected beam as far forward into the distance as possible, thus Driving Lights or sometimes called Spot Lights.
But now legality steps in, the requirements for a Fog Lamp are totally different to that of a Driving Light, and most countries with lighting legislation require totally different switching, and thus wiring, arrangement. Jaguar never listed/offered a single nor dual Driving Light option for the XK120, let alone a Fog Light/Driving Light mix, albeit I am not saying cars prepared in their Competitions Department may not have had such alternative arrangements depending on the intended event/usage. Similar situation in the post-factory, aftermarket situation - both SFT and SLR lamps were readily available from Lucas or Lucas Dealers direct, or from various other outlets, so very easy/simple to fit whatever you wanted, and switch and wire it all up however you liked, with variable levels of knowledge/competence and dare I say care about the legalities of the after-market installation.
But thus the proliferation of Fog/Driving Light brackets now seen - for my money only those as photographed by GROWLER look factory XK120 correct to me, thus I am pretty happy with Robs drawings albeit maybe some minor tweaks. Whether GROWLERS total installation was an original factory twin Fog Lamp installation or not its hard to say, most probable I think given the brackets, grommets, fog lamp switch and position of the grommets and the switch. But who knows when the Driving Light or just the Driving Light lens was modified/added, and indeed how well or otherwise, legal or otherwise, was the switching/wiring to suit addressed given the legality varied country to country, and actually evolved during the XK120 period with Jan 1952 very much early days.
So I want to see full details/dimensions of every aspect of GROWLERS installation, being as far as I am concerned undoubtedly the best/likely original road-car installation so far found - LOVE IT!
This is the XK120 I owned. Bought in Australia and then restored starting in Australia and completed in Germany. It came with all the bits you see in the picture I sent to the JDC Magazine in 1991 and published in 1992. The Lucas “Flame throwers” came with the car as did the mounting brackets. I don’t know if this helps at all, but that is how I inherited it.
Very cool car, Karl. The “Flame Thrower” SLR 700S Long Range Driving Lamps are a period-correct accessory. I suspect they greatly boosted the rather anemic light output of the 7.7 inch Lucas Tri-Bar headlamps. It appears they’re mounted using the Lucas brackets that Bob Knijnenburg showed at the beginning of this thread. Were they switched by the chrome knob, Lucas 031216 pull switch that Bob K. shows in his photos?
Here is a diagram of the dimensions of the hole for the fog light wiring.
As you can see I do not do CAD drawings as a day job! but the information is there.
Absolutely not to scale.
If these were indeed an original factory setting, it is my best guess that this car was originally fitted with one spot and one fog and the two symmetrical chrome knobs (on/off switches) on the dashboard were for fog and spot separately.
However if there is no evidence that the factory ever fitted spot lights then a less pleasing explanation is that the spot light was fitted later. On this car
there is no evidence that the fog and spot were wired separately, something that would be illegal today.
Looking at what uploaded, tell me if it is illegible and I will redo.
Growler,
Completely clear (see enlarged pic below). I took the liberty to change your text “head lamp hole” into “bumper bolt hole”. I’ll have a look how your dimensions compare with what we figured out.
Thanks for your input.
Bob K.
This is most useful, thanks