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MG parts spares and accessories are available for MG T Series (TA, MG TB, MG TC, MG TD, MG TF), Magnette, MGA, Twin cam, MGB, MGBGT, MGC, MGC GT, MG Midget, Sprite and other MG models from British car spares company LBCarCo.

MG TD TF 1500 - P L Tripod headlight bulbs

Has anyone had any problems lately with the PL Tripod headlight bulbs?

Last summer I purchased a set of PL Tripod lights from Moss and installed them in my '53 TD because I preferred the classic tripod look. Two weeks ago I had to use the headlights for the first time and when I turned them on both bulbs immediately blew. I hit the dimmer switch and was able to get the low beams to come on long enough to drive the mile home and then they quit as well. At first I thought my problem was with my dimmer switch so I changed it and still no lights. I carefully studied the wiring diagram and realized that as long as the the high beam indicator in the speedometer was working properly I was getting power past the dimmer switch. I brightened up my ground path connections and still no lights so I checked the bulbs and sure enough they were both blown.

I talked to Moss and asked if any problems had been reported and they said not that they were aware of. So I ordered 4 more bulbs.

I'm wondering if anyone else has had this problem and secondly what the cause might be aside from faulty bulbs or rough handling during shipping. The bulbs are marked made in the PRC which probably explains the problem but I'm wondering if there might be something else in the vehicle I'm overlooking ???

Thanks in advance for any feedback.

Art Todd

Could be that you were supplied 6 volt bulbs in lieu of 12 volt.
Sandy
SANDY SANDERS

art, have you checked what your ystem voltage is? regards, tom
tom peterson

Hi guys,

The bulbs were marked 12 volt and my system is a 12 volt system. I replaced the 12 volt sealed beam units (which worked fine) with the P L tripod lamps. I'll try the new bulbs I have on order and see what happens. The failed PL bulbs really had a lot of discoloration on the inside which looked like it might indicate an air leak.

Thanks for your responses.
Art Todd

I assume these to be quartz-halogen bulbs.

In my case, I found that after a year of use, the enamel in the centre of the tripod, became baked, I assume from high heat, and broke up.

For that reason, and because IMHO they're better, I switched to Sylvania Silver Star lamps.

Gord Clark
Rockburn, Qué.
Gordon A Clark

Probably el cheapo bulbs considering the source.

Check your voltage to be safe. At high revs, one TD here registers 15.9 Volts. I intend to tweak the regulator since the electronic HID arc headlights spec 16V max and the pertronix ignition might not survive either.

Dark discoloration likely resulted from tungsten filament burning out vs light discoloration from oxidation due to air leak.
Jim Northrup

Thanks for the comments, Jim. One bulb actually had a fairly light colored residue and the other was both black and white so I suspect that there were air leaks. We'll see what the new bulbs do and where they came from. I will run a voltage check before installing the new bulbs as well.
Art Todd

This is just a quick update. I checked my output voltage and it is 13.3 volts and I installed new bulbs this afternoon. The lights seem to work fine so far. I do need to re-adjust them now as I did move the buckets a bit trying to improve the ground path, however. It does appear as though the old bulbs may have had air leaks.
Art Todd

This thread was discussed between 08/10/2010 and 14/10/2010

MG TD TF 1500 index

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