Mercury 90 Service Manual

3B-18 - FUEL SYSTEM 90-830234R3 DECEMBER 1997
Main (High Speed) Jet Adjustment
The carburetor has a fixed high speed jet. Extreme
changes in weather (temperature and humidity) and/
or elevation may result in a too lean or rich fuel mix-
ture at wide-open-throttle, which may require a
change in the high speed jet. A smaller size main jet
will lean the fuel mixture, and a larger size jet will en-
rich the fuel mixture.
b
a
c
a - High Speed Jet
b - Bowl Drain Plug
c - Idle Mixture Screw
Jet Orifice Size Chart
NOTE: 10-32 Thread Size
Jet Orifice
Size-inches
Part
Number
0.034 19266034
0.036 19266036
0.038 19266038
0.040 19266040
0.042 1399-5315
0.044 1395-7394
0.046 1399-5317
0.048 1395-6246
0.050 1395-6028
0.052 1395-6359
0.054 1399-5225
0.056 1399-5213
0.058 1395-7831
0.060 1395-6487
0.062 1399-4217
0.064 1399-4216
0.066 1399-4215
0.068 1395-6029
0.070 1395-6030
0.072 1395-6207
0.074 1399-3794
0.076 1399-3796
0.078 1395-6680
0.080 1395-6201
0.082 1399-3518
0.084 1399-3517
0.086 1395-5815
0.088 1395-6202
0.090 1395-6247
0.092 1395-5733
0.094 1395-8423
0.096 1399-6249
0.098 1395-7335

Mercury 90 Specifications

General

Brand	Mercury
Model	90
Category	Outboard Motor
Language	English