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MG MGB Technical - Dash light rehostat

I need to replace the dash light rehostat (sp) not sure how to spell it. Don't have the book with me. Does anyone know of another source besides Moss. It seems a little pricey.
Thanks
Bud W
S.A. White

On the principal that dim lights don't need dimming, I just by-passed the rheostat completely.
Allan Reeling

Bud. I agree with Allan. I bypassed the rheostat on my 79B and my daughter's 77B with no problems and good results. The normally dim dash lights do not, under most circumstances, need to be made more dim--the function of the rheostat. With the rheostat removed, or simply taken out of the circuit, the dash lights are brighter than with it in the circuit. Almost adequate.

Les
Les Bengtson

Agreed, You could leave the rheostat as a dummy, or even replace it with another waning light/ Actualy I have a hole there, should do something about that! Mike
J.M. Doust

I could not find one at less than Moss so I took mine apart. It was just a case of opening the body tags and it all came to bits. If you are lucky it may just be full of muck and a good clean will do it. Mine had a burn on the track which meant it was never going to work again so like most I simply moved the 'out' power to the 'in' power paired tag (R/g connected to R/w). The RHEOSTAT has double tags at each side so there are spare connectors. I find the light bright enough with direct feed but they are by no means 'bright' and can't understand why the dimmer facility was ever there, maybe MG thought it would be a neat 'Technical gadget'
Bernie
:)
B Anderson

In the 1960's, car lights were not as bright as they are today, street lights were dimmer and the few traffic lights there were, were also gentler on the eyes. People used to use their handbrakes, rather than stand on the brakes when stationary. There were no halogen bulbs, LEDs or high intensity discharge bulbs. Even the dark was darker!

So the dashboard lights were brighter relative to the night, in particular with instruments with clean insides. The dimmer was probably useful then.

There seems to be an arms race these days, trying to increase the safety of vehicles by making the lights brighter.

I had a go in a new Golf the other day with a stop-start-automatic system on the engine. The engine turns itself off when you stop. Great, but then it goes on again when you take your foot off the brake. The handbrake doesn't keep the engine stopped, foot off the brake, on goes the engine! Crazy. No wonder people stay on the brakes at the lights and dazzle the driver behind.
Mike Standring

The rheostat *shouldn't* cause the lights to be dimmer in the brightest position, compared to being bypassed. However all the cars I have had with these rheostats have been the printed circuit kind rather than the wire-wound type, and that type do have the 'brighter when bypassed) failure mode when the tracks are partially burnt out, see here http://www.mgb-stuff.org.uk/rheo.htm#4.

All mine came to me burnt out like this, I don't like things that don't work so I have replaced them, but they are expensive. I can only think POs have shorted the wiring somehow and burnt them out that way, as I've not had it happen even with extra instruments.

Not all years and markets can bypass the rheostat by simply moving one wire to the 'spare' spade on the other terminal, some markets have both spades on the instrument side already used.
PaulH Solihull

This thread was discussed between 23/04/2012 and 24/04/2012

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