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Question on instrument light bulbs

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PAUL161

PAUL161

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Is there a higher wattage replacement bulb for the instruments? I don't want to modify the system or the bulb bases. Is there any other car known that uses this type of bulb base, hopefully with a higher wattage? It seems highly unlikley to me that the manufacturer of these bulbs and bulb bases, only made this type of base socket for the MG. Any clues? /ubbthreads/images/graemlins/confused.gif /ubbthreads/images/graemlins/confused.gif PJ
 
Chris Betson is offering an electroluminescent wire conversion. Or if you're clever you could wire up LEDs instead of incandescent bulbs.
 
Inst. lights. Gesh this is a seat of the pants car. Lights are for sissies. Hehe. Prob the plastic where the light shows through is dirty, stained, or what ever.
 
www.superbrightleds.com has LEDs that you can just plug directly into the light socket. I'm planning to do mine, but dropping in LEDs take a little bit more thought than just dropping in new bulbs, because you want the LED color to match the color of the lense it'll be behind. So for the instrument lights you'd need a white or green LED... for the switch back lights green LEDs, the high beam indicator blue LED, Fasten Seatbelt, Parking Brake, and Charge lights get red LEDs... and the list goes on.

On the other hand, if you're determined to stick with incandescent bulbs, I don't think they make "higher" wattage bulbs for those sockets. Even if they did, the bulb would have to be a bit larger, and that would become a problem because a larger bulb would prevent you from putting it back into the instrument.

If you're instruments are excessively dim, I'd double check the wiring. Check that Dimmer knob. Mine's a little touchie and will go from bright enough to black in as little as a 1/4 turn.

I recently did an alternator swap in my car and that _really_ gave my lighting system a boost. The new alternator is charging at 14.4V; the Lucas stock alternator had a voltage regulator that was dieing and based on the lighting brightness different I'd have to guess it was barely able to provide 12V reliably (normal voltage from a Lucas should be 13.6V i think). If everything else is good to go in your electrical system, the dash lighting should be more than adequate with the stock dash lights. At least that's my experience with my '76 MGB.

Anyways, hope there's some help for you in all that mess...

best of luck /ubbthreads/images/graemlins/smile.gif
 
Thanks Guys, Rob, I'll check out the web site you mentioned and take it from there. Thanks again. /ubbthreads/images/graemlins/thumbsup.gif /ubbthreads/images/graemlins/thumbsup.gif PJ
 
Paul, looking at your profile I noticed that you own a 72 MGB. Isn't that a Positive ground system? I seem to recall that 74 was the year MG made the change to a negative ground system but I could be wrong.

Anyway my point is - LEDs won't work with a negative ground system.

Good Luck!
 
Huh?! I'm pretty sure it was '68 when Negative Earth was done, and are ya ~sure~ about the last bit, Bret? /ubbthreads/images/graemlins/grin.gif

Bret wrote: [ QUOTE ]
...Anyway my point is - LEDs won't work with a negative ground system.


[/ QUOTE ]
 
LEDs work with negative ground. It's positive ground you have to be careful about. You can put LEDs in a positive ground car but the LED component needs to be specifically wired for it.
 
I put halogen bulbs in my "78 Midget.
No problems and more than adequate illumination.
I got them from the Little British Car Company (no connection).
 
[ QUOTE ]
I put halogen bulbs in my "78 Midget.
No problems and more than adequate illumination.
I got them from the Little British Car Company (no connection).

[/ QUOTE ]

I would think that halogen bulbs would provide more than adequate illumination for instruments. /ubbthreads/images/graemlins/wink.gif
 
Bret, the 72 has a negative ground system. PJ
 
As others have said, you can also make sure all other wiring aspects are well-maintained. Combined with an adequate alternator and relaying the headlamps (which frees up current for the instrument bulbs along the wiring chain) you may well have enough brightness! I have certainly seen halogen bulbs which will fit in these sockets (at retail and online), but can't remember exactly where, sorry. Another caveat for brighter bulbs (of not halogen or LED) is greater heat output, not to mention extra strain on what could be tired wiring and connections.
 
Doh! /ubbthreads/images/graemlins/blush.gif Ok, ok. I messed up – I really meant to say LEDs won’t work with a “positive” ground not negative ground.

PJ, Sorry, I just wasn’t sure when the change took place so that is why I brought the subject up – just wanted to make sure you knew for sure before you (or some poor sod lurking over the thread) ordered them not knowing any better. That said the LEDs should work just find.

But as several folks have pointed out if your lights are dim you might have other issues. While the LEDs draw far less current than the normal lamps do you might be just putting a Band-Aid over the real problem. Assuming your alternator is functioning correctly you could just be seeing the common result of old wiring. Unless they are of the highest quality (MGs weren’t) over time connectors will corrode & oxidize and as they do resistance builds up. And as the resistance builds at the connection point’s heat builds as current is dropped across those connections. The heat in turn causes damage to wires & terminations and builds up resistance too. As all of this is going on what happens is your Alternator & voltage regulator have to work harder and will unless corrected cause premature failures of components or in a worst case situation the all to common older vehicle electrical fire. It’s an ugly domino scenario – but one a lot of folks don’t take into account.

Good luck,
Bret
 
The lights also appear dimmer because the inside of the instrument housings have dulled and gotten dirty. I repainted mine with a gloss white and installed 9.6V bulbs. The bulbs don't last as long, but they are brighter and cheap. But simply repainting the inside of the housing with standard bulbs made a big difference. And when was the last time you cleaned the back of the instument glass? /ubbthreads/images/graemlins/smile.gif
 
All instruments were cleaned and checked inside and out before installing in the new dash along with all new switches. All the wiring was removed from the car and replaced. All electrical fittings, bullet connectors were cleaned before refitting. The alternater produces 14.5 volts at full charge. The problem with the dim dash lights is 2.5 watt bulbs. I have found halagen bulbs but am not impressed with the heat they produce. I would prefer leds if I can find some. If not, I'll just squint at the instruments at night. I don't think there will be much night driving in this car anyway. /ubbthreads/images/graemlins/nopity.gif PJ
 
Did you bypass the rheostat?
And what about your light switch? Are you sure it is in good condition? These instruments are certainly not as well lit as modern cars, but they are useable when they are in proper working order. I've tinkered with mine quite abit and finally have them at an acceptable level.
 
My car uses E10 bases (i'm not sure about yours) I found some led clusters with the proper base, but they where too large to fit into the opening. The other LEDs I found (that would fit) were not bright enough. I've considered modifying the instrument cans to accept a modern bulb socket, but like you said ... I really do not do much night driving.
 
Someone must make those bulbs in a bit higher watage.
 
Gotta watch "hotter" bulbs there: Melts the little blue plastic ring thingie if too high a wattage. In the "older" round units, anyhow.
 
Agree Doc, heck I don't need lights in side anyway, just feel the joy all around me and they talk you you when something is really wrong.
 
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