Mechanical tach failure?

"Rob Turk" wrote in message
...

Just curious... Why would you want to get a second-hand, unknown history
instrument for $50 when the difference to a new instrument is about as
much as one long flight?!? You are going to rely on that instrument for
years to properly run a $15000 engine in a $40000 plane (guestimates..),
why not get a new one that will probably last the remainder of the plane's
life??

Rob..............

Several reasons come into play. I am not of the mind set that says, "If it
ain't new, it's junk". My Pappy always told me, "All of the cars on the road
stop with used brake parts".

1. A tachometer is not a critical instrument.
2. I will select a good quality instrument and have it calibrated.
3. At this point in my life's journey, I purchase items which will last as
long as *I* will need them - not for "the remainder of the plane's life".

The philosophy of sparing no expense simply because we are dealing with
airplanes must have limits. Otherwise, we would change oil, filters, and
sparkplugs before every flight - or other equally silly tasks. Every one of
my instruments was purchased used. In five years and four hundred hours of
flight, the tachometer is the first one to present a problem. Who's to say
that an all-new panel wouldn't have had at least one malfunction in that
time?

Rich S.