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#1 Temp gauge problem
Posted: Wed Jul 15, 2015 7:47 am
by Barry
Following a change to negative earth, and no previous problems with the temp gauge reading anything other than normal. I now find the gauge goes up to 100 and slightly beyond, but then if I just switch on the interior fan (without putting the heater on) the gauge reading immediately goes down to 70. I tried this stationary, with bonnet up, and the same result. The Kenlowe kicks in as it should.any idea what is causing this, and coud it be connected to the negative earth change...
#2
Posted: Wed Jul 15, 2015 8:32 am
by mgcjag
Hi Barry.....could possibly be the voltage regulator....are the other gauges looking ok....Steve
#3
Posted: Wed Jul 15, 2015 9:03 am
by christopher storey
Check the instrument voltage stabiliser , which is the rectangular box on the lower right corner of the let down instrument flap . The lead to the fuel and temp gauges should have an oscillating reading between about 12 volts and zero . If you are getting a steady 12 volts to these gauges, this is the problem : the purpose of the oscillation is to approximate an output of 10 volts to the 2 instruments. Switching the 2 wires will probably cure the problem
#4
Posted: Wed Jul 15, 2015 10:43 am
by Barry
Thanks guys; all the other instruments are ok, apart from the ammeter which just goes into discharge mode the more circuits you have switched on. I will check the instrument voltage stabiliser, as Chris suggested.
#5
Posted: Wed Jul 15, 2015 10:50 am
by neil4444
Hi Barry,
It may be worth swapping the ammeter for a voltmeter. See details here...
viewtopic.php?t=166&highlight=voltmeter
Regards,