Morris Minor Owners Club

...or are Moggie sidelamp bulbs the least durable electrical component know to man or woman? I seem to be replacing one of them every few months, yet I don't think I've had to replace a headlight, tail light and indicator bulb in years. They seem to transform the filament into a dark shiny electroplating on the inside of the glass. Have I just been using dodgy bulbs (Les Smith, I think) or does anyone know of a white LED version which'll last forever...?

OK, so replacing a bulb isn't the most onerous task in Moggie maintenance but it just bugs me...

If they get a mirrored finish in the glass, it often means they are overheating, but that can have many causes.
If you have an alternator, now is a good time to see what voltage the car is being subjected to. However, if your getting 18 to 20 volts you'll normally find short life on all the bulbs (and everything else too).

Typically they should last for years, but another cause of shortened life is vibration. The filament is very weak when hot so it doesn't cope too well with being shaken about.

I've just replaced one sidelight bulb - after 4 years...

I think that the combined indicator/sidelight lenses have very littl space for the bulb to cool, so that may be one of the problems (our Colt hasn't needed them replaced in 9 years!)

I have noticed that the spring insode the holder tends to stick slight corrosion on the holder causes the spring loaded contact to bind. Make sure it springs properly. If it doen't, it will allow excessive vibration (as Ray notes) and arcing across the base (not good for bulb life!)

Colin