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Old 09-06-2006, 09:15 AM   #1
chucks70
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electrical problem

Always something new. Went to leave work last night and no electric in the truck. PO installed an inline fuse where the fuseable link would be off the battery, it blew. Is 20 amp, replaced it. Truck started, on the way home it blew again. I was about 6 miles from home, replaced it again. Drove a little while, a headlight blew then the fuse blew again. Happened to have a heavy guage piece of wire which I jumped the fuse line with, started home again. Now about 2 miles from home the other headlight blew. Got home verrry carefully as I only had parking lights now. Truck still running I pulled the jumper wire off and truck still ran for about 5 min. Don't think it was running on the battery because I removed the jumper wire and when I revved the engine the lights got brighter. After a couple of minutes though the truck quit again. Put the jumper wire back on and started no problem. I have had no problems electrically with the truck for about a 8 months or so

Should the inline fuse be stronger? Could it be a bad voltage regulator(only about 8 months old)? Bad alternator?

Any help would be appreciated.
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Old 09-06-2006, 09:39 AM   #2
panhandler62
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Re: electrical problem

Fuses and links melt down from excessive current. A voltage regulator is a possible culprit if it's shorted clean through and causing excess current.

They are cheap so it seems like a good place to start.

You can shotgun the part or you can measure the output voltages and current. Since things seem to be melting down you might want to try the former -- worst case with that test is you'll have a spare.
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Old 09-06-2006, 10:09 AM   #3
jamon8
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Re: electrical problem

if it is the regulator take that nasty puke hunk of junk out of your engine bay and install a one wire altenator set up

SOO EASY!
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Old 09-06-2006, 10:26 AM   #4
cdowns
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Re: electrical problem

first place i'd start b-4 changing any parts is to disconnect and clean your ground wires// poor grounds=hi amps
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Old 09-06-2006, 09:59 PM   #5
chucks70
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Re: electrical problem

Measured volts across the battery itself, 12.8V. With the engine running voltage varied from 15.2 and 16.4. Don't know how high it should be. Removed the + battery terminal and kept running. Put it back on. OK, don't know if it does anything or not but pulled the plug wire from the alternater, kept running. Next thing put a lighter guage wire (about 20G) in as a fuse jumper and put idle about 2000 RPM for about 5 min. The wire got hot but did not burn through. About 8 months ago I added all kinds of ground wires because I was having lighting issues. How do you check amp. output on the alternater? Could this somehow be too high or too low causing this?
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Old 09-07-2006, 01:02 AM   #6
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Re: electrical problem

14.2 volts is the right votlage--16.4 is why you a blowing the 20 fuse and heating up the small wire--change regulator.
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Old 09-07-2006, 03:44 PM   #7
chucks70
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Re: electrical problem

Well, added a few more ground wires from cab to frame, cleaned up a few others and then got a new voltage reg. As of now, voltage with engine running is reading 13.8, better than 16+, also got some headlights out of my junk pile and they are now working. The test will be on the way home tomorrow night from work Keeping my jumper wire in the truck for awhile just in case.
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