3.2 speedo illumination?

[911hillclimber]

My 73T has a 3.2 engine and box in it and the box (1985) is electronic, so the speedo is too rather obviously.

At night I can barely read the thing at all.
I have the 73T lighting in the speedo iirc just 2 small bulbs as used in all the other instruments which have quite poor illumination as well but far better than the speedo.

Question:
Does the 3.2 911 have some different lighting arrangement (that I can use) to the early cars for the electronic speedo?
Thinking even of led's for the instruments.



Photo below off google, but is the same as my speedo.
Are the bulb holder's on the 3.2 loom 'deeper' so they go further into the housing/mechanism?

[sladey]

You can use the LEDs but if so you should change all the instruments as the light is quite different. The LEDs throw out a very white light. I tried them on mine and have gone back to stock bulbs

[911hillclimber]

Thank you, the original instruments with the 2W bulbs are fine at night, just the speedo is far worse.
There is still 'light' but very diminished in comparison.
It's as though the bulb is in the wrong position to reach parts that need lighting up!

I see you can get 4W in the same small design.

I don't often drive the car at night, but when I have last year the speedo was all but invisible, not good going through cameras, esp with the zero tolerance coming in, hence this thread.

[Lightweight_911]

Not Porsche but I went through a similar process with my '59 Giulietta Sprint recently - the main problem being the inability to read the gauges at night.

As part of their 'refresh' I upgraded the original 2w bulbs to 5w halogen versions (plus swapped all of the warning lights to appropriately coloured LED's) & now I can see what speed (& probably more important, what revs) I'm doing ...

[Hannibales]

Car Magic

Had the vintage white of these for a couple of years now, plug and play, great illumination, job done!

[911hillclimber]

It was your Alfa speedo post that reminded me of my speedo 'visibility' andy.
I think I'll try these out on the car.

[anglophone1]

Car Magic

Had the vintage white of these for a couple of years now, plug and play, great illumination, job done!

+1 for these- great- now have LEDS everywhere on the car- except the high beam light- too bright!!

[911hillclimber]

Parts now ordered, thank you all for you help.
Graham.

[911hillclimber]

Nothing is simple!

Put all the bulbs over to LED's, all 14 of them.
The following comments are without the engine running.
Switched on in side light/ign ON, and all are nice and bright, though the speedo is still dull from 80mph on, but that won't worry me.

HOWEVER!

When I switch to head lamp position 1 of the 2 illumination bulbs goes out and all other instruments are as before on 'side-light' position!
The small 'lights-on' green bulb stays on.

The speedo is an electronic type as the box is from a 3.2.
Seems very strange that only 1 light on the speedo goes out, the rest are fine. It is bulb #1 that goes out, right on the 30 to 60 speedo range.
Also the dimmer does nothing.

I hate electrics, always have.
ANY help most appreciated.

[sladey]

I had the same. Went back to normal bulbs

[911hillclimber]

Did you find out why?
Seems odd for just one to switch off with the head lights switching on.

[Lightweight_911]

Earthing fault ?

[911hillclimber]

First point of call tomorrow.
The instrument lights are commonly earthed, I can't recall exactly where the earth stud is, but I think behind the ash tray.
Would that be correct gents?

It is a strange thing that on the side light position the LED's all work well, I can even see all the gauges!
The instant the switch is pulled to dipped/ main beam position that one speedo bulb drops out. All the rest remain the same.
That bulb is earthed the same as all the others, so why just that one? (repeat the on/off and it is always the same bulb)

I had wondered if the light relay could do something, it is the original 1973 item, but I think all the lights would drop out if faulty. I think the feed to the inst. lights come off the one relay used for all lights.

I haven't given up on the LED's yet, but you can get 4 watt bulbs in the same housing form as the factory 2 watt bulbs. I'll use the 4W if I remove the LED's.
Race Retro is coming up, so can get some there.
Note that Sladey's had the same thing, he has the electronic speedo too.

[911hillclimber]

Cracked it, so just to finish this mini adventure off:

Checked the situation again before fiddling.
One speedo light goes off when head lamps turned on, and the 'lights-on' green lamp is always on no matter what the light switch position.

Found the earth, just under the fuel tank filler tube. This has not been disturbed since doing the RHD conversion in 1992, so cleaned the lot up and screwed back together.
Again, one speedo lamp goes off when h/lamps switched on.

Decided to swop the LED for the 'lights on' green light to a 2W bulb, leave the rest alone.
Everything works, but the small green light goes off when the headlamps switched on (!)


The dimmer does not work mind, but the instrument lights are good and clear in my darkened garage, so counting this trip as DONE.

Thank you all for your help.

[andytat]

It sounds like you have 2 bulbs mixed up.
The green lamp comes on to indicate that the side lights are on
and goes out when the main lights are switched on. It sounds like it's a
simple case of switching the bulb holders so that the bulb that doesn't
go out illuminates the speedo and the bulb that does go out is now in
the position of the green marker. My understanding is that the green
marker is there to show you that the side lights are on and that you
don't need an indication that the headlamps are on because you can
see when they are on, at night at least!
Best of luck.

Andy