Evinrude 4906B 4HP 1969, Руководство пользователя

Страница: 26 / 422

2
TUNING
2-1 INTRODUCTION
The efficiency, reliability, fuel economy
and enjoyment available from engine perfor-
mance are all directly dependent on having
it tuned properly. The importance of per-
forming service work in the sequence detail-
ed in this chapter cannot be over emphasiz-
ed. Before making any adjustments, check
the Specifications in the Appendix. NEVER
rely on memory when making critical ad-
justments.
Before beginning to tune any engine,
check to be sure the engine has satisfactory
compression. An engine with worn or bro-
ken piston rings, burned pistons, or badly
scored cylinder walls, cannot be made to
perform properly no matter how much time
and expense is spent on the tune-up. Poor
Damaged piston, probably
caused by
inaccurate fuel
mixture,
or
improper point setting.
compression must be corrected or the tune-
up will not give the desired results.
The opposite of poor compression would
be to consider good compression as evidence
of a satisfactory cylinder. However, this is
not necessarily the case, when working on
an outboard engine. As the professional
mechanic has discovered, many times the
compression check will indicate a satisfac-
tory cylinder, but after the head is pulled
and an inspection made, the cylinder will
require service.
A clean
exterior
engine appearance reflects this
owner's pride
in his unit. Keeping the interior well
lubricated and properly adjusted will give him the
enjoyment deserved for his investment.