Talk Morgan Forums Morgan Sports Cars Maintenance & Servicing Workshop note: Misting gauges 2003-6 dashboard

Tomorrow is the day I picked up my Roadster, nine years ago. I don't recall if the small gauges misted up on the way home, but they certainly did soon after! And so this has been on my list for nine years, but was not a huge priority. Today I took a serious look at the small gauges for the first time.



The temp gauge, with visible reference numbers:



At the top is a 5mm hole. But the internals are just below the hole. I've enlarged this by hand to 5.5mm.



At the bottom is another 5mm hole, also now enlarged to 5.5mm.



I've added three small holes to the top, using a pin-chuck - which is a finger drill.



Oil pressure gauge numbers:



Fuel gauge - this one appears to be Morgan specific:



And the Voltmeter:



I've treated then all the same, except the fuel gauge, which is the worst mister. In this case I've enlarged two of the three additional holes on top to about 3mm. I've also added two more holes in the back.

Finally I've added some Reflect-a-cool to the bottom section of each. just in case rising heat is part of the problem.



And as a final touch. I've added a leather "water deflector", secured with double sided tape, over the gauges and the circuit board which is fitted just below. This is a bit of a gamble, as it may reduce air flow through the gauges. Only time will tell........................

I would have thought that heating them up to drive out any moisture and then sealing them would be a better bet. Drilling holes will only let in more moist air surely.

Only time will tell Keith, but the panel light hole can't easily be sealed, and so moist air will still be drawn in.

I'm hoping to get more airflow through the interior.............

It will be really interesting to see how this pans out Dave, well done having a go in a positive direction - who knows you may end at last the years of speculation.

Interesting, Keep us posted Dave...

I have a 1993 Plus 8 and have also had misting since I bought the car some 2+ years ago. My career has been in the HVAC industry and we know from experience that the solution to condensation lies with effective ventilation. So my take on this is to increase the ventilation so I agree with you Dave in trying to increase venting the gauges. However I dont think you have done enough. I am convinced that if holes are drilled in the lenses the condensation should cease. However I am not brave enough to try this. Surely one of the specialist firms/dealers have the answer?

Fingers crossed.

Dave,
Brian Miller fitted the leather bit over mine many years ago with the standard holes they still misted. But it protects the PCB which at £500 a go for a new one is well worth it.
As you know the LED bulbs sorted the misting on all but the fuel gauge. But even that is reduced.

However driving back from the concert last Sunday was the first time I drove at night. The LEDs give a bright white light , the bulbs in the speedo the usual yellow. Also the dimmer didn't seem to do much if anything. Perhaps painting the LEDs yellow could help.

Will be very interested to see how your new holes help. How did you keep any swarf out of the gauges?

Have just bought on ebay some yellow headlight paint.
Will report back on if that solves the white light issue.

I know that Caerbont Automotive Instruments (Smiths) have had a lot of trouble with the colour of the light from LEDs for their new range of small instruments. The oil, fuel, and temperature gauges that they made for me use 4 small LEDs on the circuit boards. These LEDs (in their uncoated state) render an almost blue light and to reduce the light to a colour temperature near to the incandescent bulbs they have coated the LEDs with a special paint.

Unfortunately the end colour is not exactly the same as the incandescent bulbs which by comparison render a light which is slightly pink.

In order to resolve this oddity I have now purchased quite a few different types of LEDs. The cost is not great but the time involved is becoming quite significant. I have now found a supplier who has LEDs which have a good colour temperature, somewhat cooler than incandescent but not far from the LEDs (coated) that Caerbont have used in the small instruments. I am still experimenting a little as to the number of LEDs which would be suitable. 4 LEDs seem too bright and my next attempt will be with 2 LEDs.

The main problem is that two different size bulb sockets are used. The original 3 in 1 instrument and the clock (if fitted) use what is known as T10 size in a push in holder and the speedo and tacho use the smaller T5 size in a twist lock holder which is hidden under a rubber cover.

So far I am modifying a small circuit with 8 LEDs to experiment but when I am satisfied with the result I will ask the supplier if they can make both T5 and T10 with the specified number of LEDs and what the minimum order quantity would be.

I will keep you posted if I am able to get a satisfactory result. If it works out I will see if I can put together a kit with fitting instructions.

PS. Dave. Going back through your photos I see that the earlier Caerbont small guages used in the Roadster use the T10 bulbs and do not have the LEDs internally mounted that my small instruments have.