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Tachometer flicks 500-1000 RPM

WarWagon

Well it hits on 7 of 8...
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Tachometer flicks 500-1000 RPM - dropping out and then flicking 500 - 1000 RPM to the actual RPM for a moment. It appears a wiggle test affects things behind the alternator. So I have repaired the wireing harness that drives the tach by replacing the crimp connector with a soldered joint as the 1993 has a replacement alternator connector on it.

This worked for a week and now the flicking is back. Checked batteries and connections. Voltage appears to be 14.4v and steady when checking it while this happens. (Voltmeter may be too slow to catch anything.)

This has the CS-144 mod done. (It's outlived several CS-130's by now.) All other gauges are steady when this happens.

Ideas?

Cracked connection in the alt regulator?
 
I've had the same problem for over a year. Only mine is not affected by the Wiggley wire harness test. I went through all the grounds three times so I know that's not it.

My voltmeter did start flickering about a month ago I have not tried the regulator yet. My voltmeter never used a clicker and the tachometer started about 8,000 miles before the voltmeter started flickering.

I REALLY wish I could tell you what the problem was.
 
Maybe time to buy Leroy's device that reads RPM's from the fuel line? (I think he needs to rebuild his fuel fund for another RV road trip :D )
 
Swapped alternators. Old one had bearings going dry and clearance on the front bearing. Little corrosion at the bottom of the regulator plug.

Worked for a week and started jumping again at idle.
 
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