John:
I've had this happen to me. From your description, the tach needle operates
smoothly, it's just sluggish. If that's the case, it's likely a lubrication
problem in the instruments head, and the tach should be cleaned and lubed by
an instrument re-builder.
The way to tell - if the tach resumes normal operation in warm or hot
weather, that's the likely cause. Also note that if it's a lube problem in
the instrument head, it doesn't matter whether the tach is a cable drive, or
electric - a sticky tach is a sticky tach!
My suggestion: drive it as is for a bit, see what happens on a long drive on
a hot day. If it remains sluggish, try a new cable, if it's still a
problem, have the tach re-conditioned.
Earl Kagna
Victoria, B.C.
BT7 tri-carb
BJ8
----- Original Message -----
From: "Randolph Cooper" <RANDOLPH.COOPER@NETL.DOE.GOV>
To: <healeys@autox.team.net>; <j.adamik@comcast.net>
Sent: Thursday, May 20, 2004 4:42 AM
Subject: Re: sluggish tach
John,
Mechanical tach, right? I don't know there's anything special about
Healey tachs, but with my experience with motorcycle instrument drives,
your symptoms would lead me to suspect a problem with the drive cable.
Things like a broken strand (soon to be followed by many more broken
strands) or maybe a rounded cable end where a squared one would better
fit the drive. Universal speedo drive cables are available at all the
cut rate auto parts places for not many bucks and they can be trimmed to
fit bike applications. Probably they'd work on our cars, too.
Randy Cooper
BT7 (Electric tach)
>>> "John Adamik" <j.adamik@comcast.net> 5/19/2004 9:40:05 PM >>>
During this spring's "clean out the exhaust" run I discovered a very
sluggish
tachometer. It appears to indicate the proper rpm, but just takes a
few
seconds to get there (i.e. heavily damped). Any suggestions would be
appreciated.
John ' 62 BT7
|