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Discussion Starter #1
I have tried the search function and can not find what I need.

On my Shadow 1 (1971/2) I am looking for the details of the thread used on the oil pressure switch for the dashboard light if anyone can help.

I am planning on installing a Smiths duel oil pressure and coolant temperature gauge in place of the clock and in my other thread in here it is mentioned that another user tapped into the original dashboard oil pressure switch with a tee to then feed both the switch and the oil pressure side of the smiths' gauge (mechanical capillary tube type)

Before I start taking things apart, I want to get all the parts together, but to order a Tee and therefore the right oil feed tube, I could do with the thread specification/type.

One I have all the parts together, I plan on taking lots of photos of the whole process and putting together a bit of a how-to thread if it is of interest.

I am also thinking of changing the switch at the same time as it is approaching 50 years old, but I am also not sure if the part crosses over to a less expensive identical part. I have seen mention on the forum while searching for information, that the Shadow 2 switch which also cuts the fuel pump crosses over to

I have seen in here some threads mentioning the switch, along with a mention that in the Shadow2 cars it is mounted in the oil filter manifold, so I am presuming the shadow 1 is the same, but I am not sure if this same part crosses over to the Shadow one with just the dashboard warning light, can anyone shed any further light on this or provide an alternative part number?

Many thanks in advance.
 

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Why in heaven's name would anyone "go back" to using a capillary tube method?

There are plenty here (and on other RR forums) who have introduced an oil pressure gauge into the mix using a conventional electronic pressure sender. I know that's been documented on these forums and that's the direction I'd suggest you go.
 

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Discussion Starter #3
All I wanted was an electrical dual oil pressure and coolant temperature gauge.
Easy to get an oil pressure gauge in electrical, easy to get a coolant temperature gauge in electrical, getting a combined all in one, especially not something from "Knight Rider Industries" but something that looks in place seemed to be impossible, despite hours searching.

Someone here had a Smiths dual gauge installed in place of the clock, and it looked in keeping, other than it looked a bit busy with the pressure and temperature being in numbers, but even this was capillary driven.. So I ended up buying a Smiths GD1301-21C072 which is the same unit, but in the lower half (temperature) it is a scale rather than numbers, going from C to H, which made it look less busy, but still capillary driven.

Here is a picture.
28432


Which I plan to replace the clock with in my Shadow1.

I prefer electrical, even though some say mechanical is quicker in responding or more accurate.

But all I could find in "oil pressure" and "coolant" in one gauge was capillary... Now I just know someone is going to find one and post it on here, and truly spoil my day!

All t he best
Jon
 

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Discussion Starter #4
Why in heaven's name would anyone "go back" to using a capillary tube method?

There are plenty here (and on other RR forums) who have introduced an oil pressure gauge into the mix using a conventional electronic pressure sender. I know that's been documented on these forums and that's the direction I'd suggest you go.
Out of interest though..... If I were to have an electrical oil pressure gauge, where would you screw in the sender? and what thread specification is it? :)
 

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Thank you,

Jim Walters answer to my old resurrected thread on fitting a temperature and oil pressure gauge was instrumental in my choice of the gauge I have, the only difference being mine has a graphic "cold to hot" to easily differentiate between the temperature scale and the pressure digits from the corner of the eye glances when driving. But both are capillary.

I think I had read the Australian thread a year ago when I was first thinking about this little project, I remember thinking "no not after the thermostat in the elbow!" and some of the argument in there about if a coolant temperature oil pressure gauge was necessary, as well as thinking that if everything was about "the necessity" and function, rather than comfort and reassurance, nobody would have ever purchased a new Rolls Royce and we would be talking about agricultural Land Rover maintenance instead.

Mentioning carefully noting what Jim says in regard to the oil pressure setup, had me second-guessing if he had mentioned the oil pressure switch thread he used for his tee, I have re-read it several times check, but alas no.

I did ask in that thread in here, if Jim remembered the thread type for the oil pressure switch, so I could buy or make a similar adapter/tee as he used, but not having a reply I thought I would ask the question as a specific thread (This one), as from a detailed search of both this forum and the Australian forum, and various parts diagrams and other threads in both forums, I could not find the answer.

I run quite a busy workshop and my cars are a lower priority for time on a lift, so I often need to prepare all the parts I need in advance of taking the car apart, so if someone had the information I needed on the thread type of the oil pressure switch I could take some steps towards being able to be prepared, as the next time it is on the lift, I will be changing the water pump, fitting a new thermostat (which will probably be trial fitting a couple of different alternatives), machining up a new triangular plate for the coolant temperature bulb, and hopefully fitting a tee into the oil pressure switch so I can fit the combined coolant temperature and oil pressure gauge.

What I might do is order a new oil pressure switch, this way I can identify the thread, post details of it here for anyone searching in the future, as well as renewing a 40-year-old part all at the same time.

Thanks for your advice, I will keep everyone posted with the answer... Nothing worse than searching for the answer, only to find several people in the same boat, but then finding they never return with the solution :)
 
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