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Head light Help

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Gordon_Dedrick

Gordon_Dedrick

Jedi Trainee
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Put a set of PL700 reproduction headlamps on my TR3. LOVE the way they look, but I have had TWO sets of halogen bulbs fail after a short period of use (1-2 hours). They are H-4 55-60W bulbs and I was carefull not to touch them before in stallation. Any ideas? I REALLY would like to drive at night......at least SOME!!
Gordon
 
Don't know how true it is, but I've heard that halogen bulb life can be extremely reduced by running them on less than rated voltage. You might check how much juice is actually getting to the bulbs.

On my TR3 the ground to the body was losing 0.5 volts, plus another 0.5 or so through the wiring and switches, plus another 0.3 or so at the connector. The bulb was getting less than 11 volts with the battery at 12.6.
 
Filament or envelope failure?

Randall posted the most likely cause. We've run H4 lamps in all our personal LBC's for three decades, only early filament failures were due to low voltage. Usually due to poor ground issue.

For the enclosures, I wipe them off before installing with a soft cotton cloth and isopropyl alcohol.
 
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