Mounting instruments to panel

[RHaughton]

Evening all,

Does anyone know how an instrument should be mounted to the dash panel besides the fixings? Should it be sealant, a seal, or just left bare - metal to metal?

Many thanks

[Wittsend]

Metal-2-metal. Instruments are held in place by a "[" shaped bracket fixed to the back of the instrument with 2 thumbscrews. No sealant or anything else is used or needed. After market temperature/oil/amps/volts 2" "Smiths" accessory gauges are fixed in the same way.

If you have lost these brackets you can make your own from a strip of steel, using a cardboard template to get the length of the arms right.

[diffwhine]

Pretty sure Embertons do them

[RHaughton]

Hi, thanks for you reply - sorry shouldve made myself clearer - I have the brackets etc however I was wondering how the seals are used. What is there a seal that goes between the obverse of the bezel and the front of the dashboard plate?

Many thanks

[Larry S]

There are 3 seals per each gauge. One of wich does go between the bezel and dashboard.

[diffwhine]

I'm inclined to agree with Larry.
This photo is of the instrument panel for a 1963 LR in Southern Africa. Logic says that there would be a rubber "gasket" between the mating surfaces originally - especially given how many of these were used in such environments open top.

And yes - I do know it looks like it has the wrong fuel gauge in it. I haven't investigated that bit yet.

On this one, the ambient heat appears to have liquified the seal and its spread out. My 1965 SW did something similar, so I always assumed that there would have been some sort of seal there, but over the years, they either disintegrated or when horrible.

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Of course, this could also be the seal between the bezel and the glass pushing out?

[Clifford Pope]

I've always assumed instruments sit on a rubber seal, and most old cars I've owned come with the seal showing signs of perishing (although never quite as bad as in the picture!)

[RHaughton]

Thanks all - I've also read in a few different places that there was some sealant used originally, however it's best to use a rubber seal these days.

Many thanks

[GlenAnderson]

A large square section rubber O-ring goes between the instrument and the dash panel.

They do degrade with age and exposure to UV, which makes them sticky, which can give the impression that there's some kind of adhesive or sealant on them, but they would always have been installed dry.

[diffwhine]

And this proves it. Found in my stocks this morning.

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[Larry S]

*** rewrote post, hadn't had my coffee yet and really messed it up. Sorry. ***

A large square section rubber O-ring goes between the instrument and the dash panel.

They do degrade with age and exposure to UV, which makes them sticky, which can give the impression that there's some kind of adhesive or sealant on them, but they would always have been installed dry.

Correct.  In the picture I posted above you can see a length of o-ring material. It is a round o-ring used between the bezel and glass.  From what I learned while researching these, the original o-rings, made of mastic, provided a better seal when mating to the glass surface in such applications, same with the windows.

The original bezel seals did ooze over time and get then crusty and hard. The o-rings I used are made of a material that mimics the original mastic, but won't ooze or harden over time.

When the originals started oozing the mastic could also get under the glass as well.

Sorry for the blurriness of the 1st pic, it's the only one I could find quickly showing the ones in Grover before restoration.

The o-ring between the gauge housing and dashboard is a rubber square o-ring.