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Checking Alternator

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Old 01-02-2008, 09:34 AM
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Checking Alternator

Is there any easy way to check the alternator to see if it might be going out? My voltmeter has always set at about half way and the last couple of weeks I have noticed it almost at the 3/4 mark even running down the highway. The truck still seems to crank okay but I don't want to take a chance of getting stranded somewhere towing the 5th wheel.
Old 01-02-2008, 11:44 AM
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Get a voltmeter that plugs into the cigarette lighter. Walmart has them for $15. Mine averages around 14.5v.
Old 01-02-2008, 11:49 AM
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I have a Pioneer Navi Screen (AVIC-N4) that reads voltmeter, but you have to coin out the dough for the screen. Mine also reads 14.5-6 on the road. When the grid heaters cycle it drops to 12.5 volts then back up to 14.5. (Crazy to watch it jump on the voltmeter.) But any voltmeter like stated above^^^^ will give you an accurate reading.

EDIT: On another note, you could always just stop by any parts store and they will check your batteries and alternator for free.
Old 01-02-2008, 12:30 PM
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In the cold weather my gauge always goes over to the right of half a good ways. My company truck 01' Dodge Durango does the same thing in the cold weather. Just thought it was a Dodge thing and never really worried about it.
Old 01-02-2008, 01:40 PM
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My first thought was the grid heater but this is running down the highway at 65mph towing our 5th wheel and outside temps in the 60's.

MikeyB, I have to go to Walmart in the next couple of days so I will pickup one of those cig lighter volt meters and see what I get.
Old 01-02-2008, 04:28 PM
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Maybe I am just being over cautious on this. I checked again a little while ago when I ran up to Home Depot and the gauge is maybe 1/8" to 1/4" past the middle which is 14 volts. Is this about right running down the highway and warmed up?
Old 01-02-2008, 11:49 PM
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A typical 12 volt charging system operates at aroud 14.2 to 14.4 volts, you could have a battery that is sub standard, you should have the batteries load tested, then go from there.
Old 01-03-2008, 07:07 AM
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I am going to stop by Auto Zone this morning and have them check the charging system out.
Old 01-03-2008, 10:52 AM
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I had the batteries and the altenator tested and they all check out. Maybe I just have a flaky voltmeter. I did clean the battery post and cables when I got home so maybe that will help.
Old 01-03-2008, 12:27 PM
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I think mine reads high when in Buda . My 2meter transmitter typically reads around 14.5 as with the other guys.

Pete
Old 01-03-2008, 03:30 PM
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Mine does EXACTLY the same thang. I checked evetything. All is good. I do however feel that my batteries might be getting alittle old. They do load test OK though. My gauge needle lays on the right edge on the number "4" this time of the year!! Sounds just like mine.
Old 01-03-2008, 07:08 PM
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On a side note the people in Canada are going to see slightly lower readings because of the day time running lights!
Old 01-03-2008, 09:00 PM
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Originally Posted by Red-Goat
On a side note the people in Canada are going to see slightly lower readings because of the day time running lights!
If the voltage reg is working properly there should be no difference just because the lights are on.

Peterbilt:: What kind of 2meter transmiter and where did you mount it??
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