[PAAirheads] Electrical Gremlins

[Larry A. Mansfield]

A couple of weeks back I had charging system issues on my R90S. Really 
confusing.  I'd replaced the stator, the rotor, the voltage regulator, 
and Diode board and thoroughly cleaned all connections.  The system was 
only putting out about 8.5 to 9v back to the battery.  Not good.

Went through all the normal tests.  Rotor tested out fine. Stator tested 
out nicely.  All three leads from the stator and the Y lead were 
correct.  The voltage regulator test with a jumper showed low voltage to 
it.  Diode board also tested fine.  Totally confusing.  Then with the 
alternator assembly off I tested the continuity on the brushes.  Bingo 
on the brush assembly.  Both sides were grounding out to the stator 
cover, aka continuity.  D- should, DF or D+ shouldn't.  Looking the DF + 
side over I finally found the culprit.  The fiber washer on the inside 
had chunked and it was allowing the nut on the post to ground to the 
cover and the case.  Enough to affect the output voltage.  Removed the 
brush assembly and put new fiber washers on inside and outside. Charging 
system back to full output.

Wanted to pass that along as an additional test to do if you experience 
electrical issues.  A test that isn't normally mentioned.  Usually the 
brushes are considered the issue.

larry m