Jet Pump Unit - Yamaha GX1800A Service Manual

Major changes
8 Thermostat
9 Cooling water passage
10 Premium gasoline

Jet pump unit

The jet pump, jet intake and jet nozzle have been newly designed to correspond to the higher output
engine.
The jet pump components have been improved in strength and optimized for better functionality to
handle higher output.
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Thermostat valve opening temperature has been changed to
optimize engine temperature and to reduce pollutants in the
exhaust gases.
Cooling passages through exhaust manifold and exhaust man-
ifold gasket have been optimized to reduce thermal load.
Provides better anti-knock property to correspond to higher
engine output.
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5
5
16
Description
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3
2
Technical tips
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