burned out headlight
- jeeptj1
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- Location: Illinois
burned out headlight
second time in a year the passenger side headlight has burned out. checked the grounds and they appear good. scraped and made bare the ground connections. probably only had the lights on a half dozen times or so. thanks john jr
- Bretto
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- jeeptj1
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- Joined: Thu Aug 19, 2010 6:00 pm
- Location: Illinois
headlight
well I guess I could just swap the headlights and burn another thirty dollar one out. sorry if I didnt make it a question. Lets try this. Would anyone have any ideas on why the headlight would burn out with such short time usage on it.
- Balvar24
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- RimfireJim
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The poor ground problem with regard to burning out headlights happens when there is a poor ground for the charging system, causing it to over voltage, not when there is a poor ground for the load (lamp). A poor load ground will just impede current flow and cause the lamp to not light.
Check the voltage of your charging system at driving rpms. The headlamp may just be the weak link symptom.
Check the voltage of your charging system at driving rpms. The headlamp may just be the weak link symptom.
Jim M.
1952 M38 son-father project
Discovering more worn out parts, one assembly at a time
1952 M38 son-father project
Discovering more worn out parts, one assembly at a time
- wesk
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Frequent head lamp failures have several causes.
1-Voltage too high. Check generator output with a digital VOM at about 3000 RPM. It should not be more than 28.5.
2-Check lamp retainer system. If lamp or grill is loose and free to vibrate the filaments will often break.
3-Cheap lamps. No namers and those that are not Westinghouse, GE, Wagner or Phillips.
4-Loose grounds lead to rapid voltage spikes that will overheat filament quickly.
As for causes of high voltage from generating system there are many more causes to investigate there than just poor grounds.
1-Voltage too high. Check generator output with a digital VOM at about 3000 RPM. It should not be more than 28.5.
2-Check lamp retainer system. If lamp or grill is loose and free to vibrate the filaments will often break.
3-Cheap lamps. No namers and those that are not Westinghouse, GE, Wagner or Phillips.
4-Loose grounds lead to rapid voltage spikes that will overheat filament quickly.
As for causes of high voltage from generating system there are many more causes to investigate there than just poor grounds.
Wes K
45 MB, 51 M38, 54 M37, 66 M101A1, 60 CJ5, 76 DJ5D, 47Bantam T3-C & 5? M100
Mjeeps photo album: http://www.willysmjeeps.com/v2/modules. ... _album.php
45 MB, 51 M38, 54 M37, 66 M101A1, 60 CJ5, 76 DJ5D, 47Bantam T3-C & 5? M100
Mjeeps photo album: http://www.willysmjeeps.com/v2/modules. ... _album.php
- jeeptj1
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- Joined: Thu Aug 19, 2010 6:00 pm
- Location: Illinois
thanks guys
thanks guys, i will check out the voltage items. just got back from train trip to grand canyon. thirty one hours but it was worth it. john jr
