In a message dated 97-01-14 15:59:02 EST, you write:
<< Rich Mason wrote:
> > The only internals that were not replaced were the needle and jet,
neither
> > of which I thought of as "wear items" when I ordered the original parts
for
> Rich, I never thought of the needle and seat as wear items either. >>
Ron, Rich is correct the needle and JET are wear items on the HIF and late HS
series carburators; those with the "biased " needle.
Unlike the earlier carbs, the late HS and HIF needles actually rub against
the side of the jet. This is why there are no instructions on centering the
needle as on the early units. Because of this contact, the needle will
gradually flatten on that side that touches the jet, and likewise the jet
itself will wear into a pear shape. Both conditions will gradually lead to an
enrichening of the carb mixtures until ultimately it is impossible to tune
them. Most manuals recommend replacement of needles and jets at about 20,000
mile intervals. Personally, I do it much like clutch replacement: If the carb
is off and apart, for whatever reason, I'll get a new SET of needles and jets
along with the repair kit.
My £.02 worth
Rick Morrison
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