Tachometer Modification.....

#1
....for my Oxford.
I've long had the idea of adding a tachometer to my Oxford by extending the existing dashboard trim using another, like this:

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The chap who has modified his Traveller beat me to it though he hasn't got the tachometer working yet. He did give me the pointer to a matching dial face though (l was just going to fit an MGB one l have as is) by using a Riley 1.5 instrument, though these are cable driven & though he had a dynamo that has a drive fitted for this purpose he found the drive directions were opposite. As they're all the same size I thought l could fit the Riley face & pointer to the MGB mechanism, which you can but not surprisingly the rev' measurements are differently spaced & though you can re-calibrate it, l'm not sure if there is enough calibration available in the works. Anyway this is where l've got to so far:

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The MGB one came apart quite easily:

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The glass in the Riley one was so firmly stuck in & such a close fit that l had to break it to get it out:

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The teaspoon method to pop the pointers off:

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The fixing screws are in opposite planes so removing the MGB's ignition light lens & enlarging the hole just a little to centralise them together l used the existing holes in one to drill new holes in the other:

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I have it in mind to use the Riley ignition light for an oil light which the Oxford doesn't have so l cunningly melded the two light 'tunnels' together:

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The Riley screws can fill the original holes & this is where we stand:


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The pointer isn't pressed home yet as adjustment to the centre hole may be needed.

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Any advice as to recalibration welcome but to be honest it's not essential to have it entirely accurate but it would be nice. I suppose Speedy Cables could take care of it which l may resort to depending on outcome & price (l haven't tested the MGB one recently anyway) but it would be a coup to sort it myself.
 
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#3
Funnily enough the odometer isn't working though the trip is. I just bought what certainly looks like a NOS speedo from the bay for a very reasonable sixteen & a half squids.
 
#4
I've e-mailed Speedy Cables to ask about the calibration issue. Meanwhile l've done a little tidying up of the dial, just touching up some white patches where the pointer has been contacting the face. You may have spotted my adjustment of IGNITION into OIL for the red light too, albiet upside down. I can live with it anyway. ;)
The Riley's glass support ring & dial surround were better than the MG's so l used them after a quick flash over with black paint & chrome polish respectively, with a few dabs of silver for the MG screws. I'm quite pleased with it.
I won't try fitting the pointer until last thing as l don't want to have to remove it again if l don't have to. I have been thinking of running it with Dymo labels at two or three points to indicate correct readings but we'll see what Speedy Cables have to say before that:

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cobraboy

Well-Known Member
#5
Nice job
Instead of having an inverted OIL you could have had a NIT light, when this comes on it means you've forgot to add oil and have lunched the motor.
 
#10
Ah, thanks very much, l'll have a look at that. Had a quick googly, some interesting info on here:

2 Types Of Smiths Rev Counter - Problems, Questions and Technical - The Mini Forum

....including a good link for a PDF guide to Smiths tachometers.

This sticker is on the new speedo:

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The standard A60 ratio where mine is now 3.9 from an MGB. We had Google maps running on the way home from Yorkshire & the difference in readings between the current speedo & the speed shown on maps was around 5mph which is about the same as my 75 & my wife's fester so l don't think there's much of a difference made by the changed diff unless it was extremely accurate before the change or overeading by 10mph. :)
 
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