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[oletrucks] False high temp gage reading

To: Oletrucks Board <oletrucks@autox.team.net>
Subject: [oletrucks] False high temp gage reading
From: B&A Kettunen <bekett@uslink.net>
Date: Thu, 17 Aug 2000 20:57:27 -0500 (CDT)
>From time to time several of you have posted that your temp guage says your
oletruck is overheating when it really isn't.  I found one cause.

If the voltage relay is set too high on the voltage regulator, once the
battery is fully charged, you get too high a voltage from the generator.
This makes the temperature and gas gage read too high.  On my 57, the temp
guage should read rock steady just below the center, but it suddenly
started reading just below the top peg.  It would fall back when the truck
was idling at a stoplight and the ammeter dropped off.  It all went away
when I put in the alternator, but would probably be fixed too if the
voltage cutoff relay cut back the generator when it should.

If this happens to you, a reading with a voltmeter should tell the tale.
With a fully charged battery, the voltage should be no higher than 14.5
volts when the engine is running fast enough to generate some amps.

In the long run, this would probably also fry the battery.  In the old
days, the battery would loose water, but with the maintenance free ones
nowdays, it's hard to tell until the battery fails early.

Now that I know what to look for, the service manual covers this in detail.

Bruce Kettunen
57 3200
Mt Iron, MN


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