Round gauges fogging up

[jonathand]

Hi,

My 3 round gauges have a tendency to fog up when I've been driving a while whenever the ambient/outside air temperature is low. My first guess was that warm air from the heater vents directly below was escaping and heating them up causing condensation. I've removed the vents and replaced the foam seals around them (which were pretty brittle and deteriorated), but that hasn't made any difference. Just wondering if anyone else has had this issue and managed to resolve it?

Many thanks,
Jonathan

[rip]

This is common.
I read somewhere that drilling tiny holes in the top allows the air to circulate. I tried this & it helps a little bit, but not much.
Geoff (Smith) then came up with the idea of taking this one stage further by fitting heater pads to them to evaporate the moisture. I am not sure if he actually did this but it sounds like a good idea.

[jonathand]

Thanks for the reply rip, comforting to know it's not just a problem with mine. I might give the vent holes a try next time I have the gauges out. Cheers

[lotusflasherman]

You have a 2 watt heater already installed - it's called the bulb. Run with sidelights on & instrument dimmer set right up for a while and it should clear.

I used to have the turbo boost gauge mist up in earlier models but the current car has the instrument lights on the ignition for some reason, so are on all the time. This has created a different problem.
I haven't yet investigated if a previous owners did a wiring mod to achieve this but am in the process of replacing faces with silver Lochwood as the black now let light through, I think due to heat from bulbs always on .

dials.JPG

Bulb has gone on Voltmeter but it's just the same when bulb is working. If I can't find the wiring mod to remove I'll run with the dimmer set right down for daytime running.

[GeoffSmith]

… the current car has the instrument lights on the ignition for some reason, so are on all the time. This has created a different problem.
I haven't yet investigated if a previous owners did a wiring mod…

It's one of the S2 improvements: To try to stop the dials misting up.

[lotusflasherman]

… the current car has the instrument lights on the ignition for some reason, so are on all the time. This has created a different problem.
I haven't yet investigated if a previous owners did a wiring mod…

It's one of the S2 improvements: To try to stop the dials misting up.

Thanks for that very helpful comment Geoff. It will be in my factory loom then so I'd better start looking at the S2 wiring diagrams from now on if that's the case.

I think I've got the last SE to leave the factory - Handbook says Lotus Cars did the Pre-Delivery on 7/12/93, was Purchased on 17/12/93 by Elf Oil UK Ltd so Registered with DVLC as 'L1 ELF' on 22/12/93.
VIN ends NHD16727 which doesn't appear on the Golden Gate Production chart or anything else I've been able to find. Think they might have built it from bits around the factory prior to the run of S2's so may be a bit ad hoc.
I have found a few things that are slightly different to my 91 SE, which confused me as I thought the changes were mainly sorting out early production/design issues in 89/90 and 91, 92 & 93 would be the same.

Have your S2 dials shown any sign of starting to let light through?

Phil

[Brit-Car-Nut]

There was a service bulletin directing all late built SEs should be converted and your's is probably one that got missed?

LFM, I would look at the attached directions and see if that is all Lotus did to make trhew S2s lights come on with the key and you should be able to reverse it.

Dash-Lights-With-Ignition.pdf

[jonathand]

My SE is a late production 92 car, and also has the dash lights on permanently with the ignition. That sadly doesn't stop the dials fogging up. My Boost gauge is letting some light through the black face, but the other two are fine.

[Brit-Car-Nut]

I was hoping the instructions for making the "improvement" could be followed and reversed so anyone that has ignition on dash lights can make the dash lights only come on with the head lamp switch without a lot of rewiring or cutting.

[lotusflasherman]

I was hoping the instructions for making the "improvement" could be followed and reversed so anyone that has ignition on dash lights can make the dash lights only come on with the head lamp switch without a lot of rewiring or cutting.

My 91 SE is prior to that Service Bulletin (09/12/91), as was my previous 91 SE, so I'm used to, and expect, instrument lights to be on light switch.
It was bit of a surprise that the Dec 93 SE had instrument lights on all the time but clarified in Service Bulletin you posted. Thanks for that.

Reading the SB it suggests that small screwdrivers are used to prise out the cable from cavity E6 of the Rheostat Module base and insert a loop to pick up an ignition supply from the base of the Mirror Heater Timer module. In theory you should be able to reverse engineer this mod' but in my experience of modifying electrical wiring on these sort of terminations is that the plastic 'key' that holds the cable in place is designed to let the cable in but not out and after cables have been prised out a couple of times the chances of ending up with a reliable connection in the relay base is slim. Might work at first but swap the Rheostat module later and the cable may get pushed out past the damaged key.

I'm planning to run with my rheostat set down daytime to stop the heat damaging the paint - have now swapped to silver faces as the black let so must light through at night I couldn't read the gauge, and when the hoods down in sunshine and I wear sunglassess I can't read the black speedo. Black gauge faces were also peeling at the edges due to heat from bulbs on all the time - see photo. I posted a photo earlier in this thread that showed light coming through the faces.

dials4.jpg

I have a spare set of early gauges and instruments that I was going to convert to silver but decided to keep them in case I want to revert and convert the 'heat damaged' '93 gauges. Spare voltmeter shown in photo - looks like new!

If you don't want to run with the rheostat dimmer set down you could insert an On/Off switch to control instrument lights using one of the spare blank switch positions just below the instrument cluster. Should be much easier than trying to reverse engineer that SB modification.

Phil