MB HEADLIGHT BURN OUT

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RMarchi
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MB HEADLIGHT BURN OUT

Post by RMarchi » Tue May 30, 2017 2:39 pm

I have a 45 Willys. The headlights have both burned out. They were brand new had only had approximately 10 to 20 hours of use.

Why did they burn out?

What do I do to fix it?

Thanks, Rob


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Re: MB HEADLIGHT BURN OUT

Post by Joe Gopan » Tue May 30, 2017 2:54 pm

Check to see if mounting brackets are secure, vibration is rough on headlamps. Another concern is quality. What brand and part number. One more consideration is excess charging voltage, are you using 8 Volts?
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JIMN
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Re: MB HEADLIGHT BURN OUT

Post by JIMN » Wed May 31, 2017 9:04 am

Are you sure it's the bulbs?
It could be the main switch or the dimmer switch or wiring.
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RMarchi
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Re: MB HEADLIGHT BURN OUT

Post by RMarchi » Wed May 31, 2017 9:08 am

I'm not sure on the make of the bulb. The brackets are tight.

No idea on wiring or switches being the issue. How do I figure that out.

Thanks VERY MUCH for the help!

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Re: MB HEADLIGHT BURN OUT

Post by artificer » Wed May 31, 2017 9:41 am

Rob wrote:1. Why did they burn out?
2. What do I do to fix it?
1. Put a voltmeter across the battery terminals & rev the engine.
What generator voltage do you get?
Be aware that is the voltage the headlights are running on & if too high it WILL burn out headlight bulbs regularly.
2. Reduce the voltage by adjusting the voltage regulator to the correct value e.g. 7.2-7.4V for a 6V system.
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Chuck Lutz
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Re: MB HEADLIGHT BURN OUT

Post by Chuck Lutz » Wed May 31, 2017 9:58 am

Some of the repop headlamps are crap...otherwise you probably have a problem that would best be sorted out with artificer's checklist I think. PO may have set the regulator to put out 8 volts for an 8 volt tractor battery.
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Re: MB HEADLIGHT BURN OUT

Post by artificer » Wed May 31, 2017 10:34 am

FI:
Normally an 8V battery needs a charging rate of about 9.5V.
There has to be a differential otherwise current won't flow & the battery won't charge.
John GIBBINS Member Institute of Automotive Mechanical Engineers [Ret], ASE Master Medium/Heavy Truck & Auto Technician USA -2002 Licensed Motor Mech NSW MVIC 49593 Current 2015
TO DIAGNOSE, TROUBLESHOOT OR FAULT FIND ANY AUTO SYSTEM....
Understand how system parts interact with one another. GOOD parts can then be established & the NOT GOOD problem/s part/s isolated for repair or replacement.

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Re: MB HEADLIGHT BURN OUT

Post by RMarchi » Wed May 31, 2017 12:25 pm

I'll work it this weekend and let you know. Appreciate your help!!!

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Re: MB HEADLIGHT BURN OUT

Post by JIMN » Wed May 31, 2017 5:32 pm

How do you check the switches? Operate them over and over, often they will work properly intermittently, especially the dimmer switch.
If that fails to help you isolate the problem, you could take out a headlight and wire it straight to a battery. If the bulbs are blown, check the voltages going to them as has been suggested. If that is fine then visually inspect the headlight wiring for problems. Still not solved, then get a friend who has a meter and can help you (teach you) with the troubleshooting.
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