Talk Morgan Forums Morgan Sports Cars Classic Morgans (pre-CX) Misty instruments

Oh yes they do!

That's interesting. Mine never did in similar conditions.

Nobody is "whining" here, but someone seems to be having an hysterical fit.

On the Trads the condensating inside the instruments seem to relate to the location in the dashboard. My multi-instrument mists often, the speedometer gets some condensation from time to time and the tachometer obove the wheel stayed clear so far.
(my car is parked in a dry and insulated garage, foggy instruments happen when humid and cold condition on the run with hood down, lights on)

The cause is simple to understand. When the air inside the instruments becomes warm any humidity in the air condenses on the cold glass face of the instrument. It is exactly the same effect as the misting on the inside of the windscreen, or condensation on the outside of a cold bottle

It is probably very rare in closed sedans where the temperature is more uniform due to running the heater. It is also very rare on bikes. I have seen it on older bikes, and sometimes occurs if a bike is parked in the sun and there is moisture inside the instruments, perhaps because the transparent glass remains at air temperature but the inside parts of the instrument are warmed. I once had a watch that did it too.

Understanding the problem is one thing. Knowing how to stop it is another. The problem is well known and one must ask why, after all this time, the makers of the instruments for Morgan have not produces sealed instruments. I generally drive with the lights on and someone has suggested that more modern instruments with LED lighting would be less prone to the problem. The idea is that LEDs produce less heat to warm the air on the inside of the instrument.

Has anyone tried fitting LEDs?

- thankfully, my Aero8 does not seem to suffer from this problem.

Previously, I had a Lotus Elise 111S (heretic , I know ) for a number of years and it regularly had misted instruments even though it lived a pampered life in a heated garage.

I think, therefore that Gambalunga's explanation is probably the most accurate in terms of causation....

Both mine do it in cold weather. The smaller gauges are much worse but it passes as soon as I stop for any length of time.

As a fellow sufferer, perhaps we could turn it to our advantage. When next stopped for speeding ( which I know nobody does !! ) perhaps we could claim some dispensation when up in front of the Beak in the form of invisible instrumentation whilst adding a little joy and happiness to others lives by letting them share in our delight?

Reg

The classic cure is to put sidelights on , this puts some heat into the dials and they will usually clear in a shorter time than by letting nature do the job.

Some have drilled additional holes in the instruments to allow them to breathe, but unless you have a very steady hand and some good equipment , and the ability to clean up any swarf that lands inside the unit, it is not an easy job, and definitely not for the hamfisted.

Mine seem to mist up more when I have the heater on - which is strange as this ought to warm up the instruments as they sit above the vents oabove the gearbox tunnel. Warm air holds more moisture so if the air warms up inside the instrument the misting should disappear. Initially it gets worse.
Out in fog on Sunday and by the end of a 45 min run they had misted considerably with the heating on.
Anyone else noticed this?

Blackadder,
Yes,
but I keep telling 'er indoors that we don't have a heater, got to look after the engine old girl !!!

Reg