Thanks list, for all the advise. I bit the bullet, took the whole
thing apart, cleaned and oiled it with special ( supposedly non-
gumming ) clock oil and it performs beautifully. The standard
"factory calibration", by setting the pointer at the the dot on the
the scale, calibrated it to within a couple mph at 45 mph, according
to one of those flashing digital speed monitors along the road.
Haven't figured how to easily calibrate it at higher speeds yet, but
at least it is perfectly steady all the way to at least 80 mph.
Hard to tell what was the main culprit -- probably a number of
contributors. The needle bearing of the pointer spindle was prime
suspect which had little blobs of a sticky substance in it.
Other probable causes are, as Randall pointed out, the odometer and
trip counter ratchet drive mechanisms which were quite gummed up and
stiff. Could find any wear,even with a good magnifying glass.
A word of caution. If you plan to do this (actually a piece of cake),
be careful not to lose that tiny micro extension spring in the
counter ratchet as I did. This little spring, as far as I can tell,
is made of .005 to .007" dia. wire, a coil dia. of .125" and a free
length of about .750". Where am I going to find that? Ah well, I'll
just have to go without the trip counter, unless someone out there is
parting one out.
The link below was very helpful.
Hans, '61TR3A
http://www.scribd.com/doc/19788252/Repairing-Jaeger-Smiths-Speedometers
On Mar 16, 2012, at 7:22 AM, <wbeech at flash.net> <wbeech at flash.net>
wrote:
I have about 3500 miles on my re-built speedo, rock solid and accurate.
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