Bob,
That is an extremely good point and one that I had completely overlooked. I spoke with Fosseway just now and they are working on a solution but do not have one available right now.
So my intended helpful suggestion was in fact a dumb idea. Sorry about that. Maybe in the future but not now.
Eric
Hi Morgan:
Your description of the physical ‘delights’ of driving an XK120 show you now have great insight into what the rest of us have been ‘enjoying’ for, in my case, the last 54 years! For those of us of a generous height (6’ or taller) it has resulted in the use of trick pedals, smaller diameter steering wheels and in my case the removal of the battery wells in order to move the seating position further aft. Combine the things you have mentioned with a gearbox that is decidedly agricultural and defies any attempt at quick shifts and you have the XK120 experience. However, I would not change it for anything and the model is, in my considered opinion, a gorgeous example of automotive styling. Welcome to the group and may you derive as much pleasure from your XK as the rest of us do from ours.
Best regards,
Chris.
That’s exactly the kind of setup I was hoping for. Like hiding solid-state ignition…
Hey Bob–like you, I would prefer to keep things original, so I’m thinking I may go to school on you and tinker a bit with the Otter. I’m guessing that the closer you get the points together, the less time the Otter stays on?
Morgan,
Cannot exactly remember which way the bi-metal spring moves and how I corrected it, but if you put 12 V over the central contact and the housing you will see the bi-metal warm-up, bend and switch. The XK 120 has the older model Otter switch (the name comes from the manufacturing company: Otter Controls Buxton, Derbyshire, UK) with a brass deep-drawn cover in contact with the cooling fluid (see pic below). Later versions have an aluminium deep-drawn cover This cover is fixed to the aluminium top plate by means of three lips: take care and avoid to brake them (but even then: the whole assembly is still hold together with the 3 screws). The actual sealing is done by the cork gasket and relies on the strength of the 3 screws; nothing else. It will take some trial and error, especially as you can only test the result with the Otter switch again in place and cooling water gradually warming up.So it is better to first test whether the switch comes in too early or too late.
It is a very rewarding feeling if your Jaguar stops “hissing” after a minute or so!!
Regards,
Bob K.
Morgan,
Just noticed that I made a mistake!! It is not the 12 V that will heat up the bi-metal spring but it is of course the warming of the complete switch housing via contact with the cooling fluid. Sorry for that!
Regards,
Bob
Just the reverse. The closer the points the longer the time but that is not really relevant. Take the unit apart; put an ohmmeter across the points and immerse in a cup of hot water. This thing is just a simple switch. As the bi-metallic element heats up it opens fairly quickly so it’s not a timing thing. So watch the meter and adjust the element by bending until it opens. All this thing does is complete the ground connection to the starting carb. So most of us run a wire from the otter switch connector to a hidden switch. Connect the other side of the switch to the frame (ground). So the switch will complete the ground to the starting carb.
Could you use a hot air blower and a IR thermometer for the initial setting?
Blow, check, blow, check, repeat until satisfied?
I also installed a toggle switch to operate the hisser manually. It should be turned off immediately when the engine starts. use your foot to keep the rpm just high enough to prevent stalling until the combustion chambers warm up a bit. Any richness that causes black smoke interferes with lubrication of the cylinder walls - not a good thing. The hisser time is excessive if you wait for the coolant to warm up - you need to shut it off as soon as the engine will idle on its own.
ATTN: Chuck Goolsbee…
FUNNIEST thing I’ve read in years!!
