All Other Engine Carburetors; Jet Needle Adjustment; Adjustment Procedure - TOHATSU NB-1000 Service Manual

Jet Needle Adjustment

The 2.5/3.5 carburetor is properly adjusted when
shipped from the factory. No adjustment should
be made to the carburetor unless absolutely
necessary.
• The jet needle is held in position by a spring clip which fits into
one of four grooves on the needle. Moving the clip to a higher
groove will make the mixture leaner, and moving the clip down
will produce a richer mixture.

All Other Engine Carburetors

Covers: 5 Model
8/9.8 Models
9.9/15/18 Models
25/30 Models
40 Model
Idling Speed
5
8 / 9.8
9.9 / 15 / 18
25 / 30
40
Adjust idling speed after warm-up operation.

Adjustment Procedure

• Set the pilot adjust
adjust the engine rpm by using the pilot adjusting screw and
throttle stop screw while monitoring the tachometer.
• The engine rpm should reach maximum when the pilot adjusting
screw is within +/- 1/4 turns of the standard position.
Replace the pilot adjusting screw if the tip is worn.
1-/ 2-Cylinder
GENERAL SERVICE INFORMATION
CAUTI0N
ln Neutral
1000 RPM
950 RPM
950 RPM
1050 RPM
1000 RPM
NOTE
screw to the standard reverse turns, and
ln Gear
850 RPM
750 RPM 8 : 1-3/8 ± 1/4,9.8 : 2 ± 1/4
800 RPM 9.9D
900 RPM
25C
850 RPM
Pilot Adjusting Screw :
Number of turms
1 ± 1/4
/15D /18E : 2 ± 3/4
2 2 2
/30A 1-1/4 ± 1/4
3 4
1-1/4 ± 1/4
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