I have just replaced the 6 capacitors on the speedometer printed circuit board (PCB) as recommended in the excellent FAQs on this site (to fix a malfunctioning speedo):
http://www.brickboard.com/FAQ/700-900/ElectricalSpeedometerRepair.htm#Tips
The job went fine, I took my time, was careful, and I think I got the capacitors plumbed in correctly. However, on the test drive the speedo does not register above zero until the car is traveling at 25-30 mph, and seems to read 25-30mph less than it should after that (I have not driven above 60 mph yet, when the speedo says 35 mph). The needle is very steady -- it just reads 25-30 mph below what it should.
I used the "speedo needle removal" method to access the PCB and I strongly suspect I have thrown off the calibration of the unit -- and in the following way. In disassembling, and going counterclockwise, I popped the needle over the zero stop twice, and eventually got he needle off at approx the 140 mph mark. Then, on reassembly, I reattached the needle at the 140 mph mark and going clockwise back over the zero stop once I tried/expected to be able to go around a second time, ran into resistance, so let the needle go back to zero (and reassembled, hoping for the best).
Anyway -- long boring question short -- can anyone recommend a reliable method for recalibrating the speedo? Next weekend I intend to remove the speedo from the car again and fiddle with the position of the needle relative to the end stop. Trouble is, I clearly don't know exactly what I'm doing. Can anyone provide a reliable method for getting the adjustment right? I have done appropriate searches and haven't come across any thread that would address this -- Thanks,
Rob
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