Fuel Solenoid Adjustment; Testing Fuel Solenoid; Engine Troubleshooting - Grasshopper 721D2 Operator's Manual & Parts List

ENGINE ASSEMBLY
Item Item Item Item Item Order Order Order Order Order Description Description Description Description Description
N o . N o . N o . N o . N o . N o .
N o . N o . N o . N o .
1 100176 Engine – Kubota Diesel
2 100800* Oil Filter (Kubota 70000-15241)
3 100208 Air Cleaner
100942 Air Filter - Primary
100943 Air Filter - Inner
4 424517 Hose – Air Intake
5 603590 Muffler w/Gasket
101040 Muffler Gasket
6 643292 Engine Mount – Rt.
7 643291 Engine Mount – Lt.
8 424078 Vibration Isolator
9 253043 Whiz Nut
10 643864 Mount – Engine Lower Rt.
11 643865 Mount – Engine Lower Lt.
12 723063 Linkage Extension – Throttle Cable
13 253176 Whiz Bolt
14 253025 Whiz Nut
15 644384 Hood Assembly
16 422012 Expansion Tank
17 423154 Tie
18 821748 Hose – Tank Overflow
19 821749 Hose – Radiator Overflow
20 280260 Hose Clamp – Spring
21 644651 Radiator Mount
22 101612 Radiator
23 101080 Radiator Mount Bushing
24 644671 Grille
25 822636 Trim - Grille
Item Item Item Item Item Order Order Order Order Order Description Description Description Description Description
N o . N o . N o . N o . N o . N o .
N o . N o . N o . N o .
26 422090 Isolator
27 604805 Swell Latch Assembly
28 755121 Mount – Solenoid/Filter
29 101000 Fuel Filter
30 603350 Fuel Solenoid
31 603209 Cable Assembly
32 265610 Ball Joint
33 254434 Nut
34 180635 Clip – Conduit
35 250258 Screw
36 253020 Whiz Nut
37 253192 Whiz Bolt
38 253035 Whiz Nut
39 243240 Bolt
40 253173 Whiz Bolt
41 643866 Support – Hood Rear
42 643766 Shield – Clutch
43 271121 Flange Bolt
44 253203 Whiz Bolt
45 253175 Whiz Bolt
46 280303 Hose Clamp – Screw Type
47 101054 Radiator Hose – Upper
48 101055 Radiator Hose – Lower
49 723021 Bracket - Air Cleaner Mount
50 423165 Nylon Tie
51 721223 Shield Rt.
52 721224 Shield Lt.
53 254431 Speed Nut
* Kubota part number 70000-15241 replaces original
equipment Kubota part number 15841-32430.
32

FUEL SOLENOID ADJUSTMENT

Adjust cable between fuel shut-off solenoid
and engine fuel stop valve to provide full en-
gagement of the solenoid. The solenoid should
bottom out (be fully engaged) before fuel stop
valve fully engages stop (approx. .0625" to
.125" [1.6 to 3.2 mm] gap).
The solenoid is designed to hold the engine fuel
stop valve open during operation. When the key
is turned on, the solenoid energizes and opens
the fuel valve. When the key is turned off, the sole-
noid releases and allows the fuel stop valve to close.

TESTING FUEL SOLENOID

Adjust cable as described on previous page. This
model solenoid will not engage until engine is
cranked. Disconnect shut-off cable from fuel
shut-off lever and operate start switch. After
briefly cranking the engine and with the key
switch in the run position, the fuel solenoid
should be engaged (pulled in). If it does not en-
gage, check for a blown in-line fuse at the
starter. If the fuse is not blown, test the solenoid
as follows.
Unplug the wires leading to the fuel solenoid.
Using an ohmmeter set on the X 1 OHM scale,
connect meter leads to solenoid wires. Correct
meter readings should be:
"Comm" wire to "Pull" wire - .25 ohms
"Comm" wire to "Hold" wire - 14 to 16 ohms
If you do not get these readings or one of the circuits
reads open, the solenoid is defective and must be
replaced.

ENGINE TROUBLESHOOTING

Should you experience trouble in starting the engine,
use the following guide to locate possible causes.
Engine will not crank:
Battery is discharged.
n n n n n
Blown starter fuse.
n
05085
PTO switch is "ON".
n
Steering levers are not out in neutral.
n
Steering lever switches are out of adjustment
n
(listen for the switch "click").
A loose wire or connection.
n
Engine cranks, but will not start:
Determine if the fuel solenoid is stroking when the
key switch is turned to the start position. If it is
not, check for a blown fuse at the starter (item
17, page 45). If the fuse is not blown, check
for voltage in the black wire at the fuel sole-
noid plug while the engine is cranking. If there
is voltage to the solenoid while the engine is
cranking, go to solenoid testing in the previous
section.
If fuel shut-off solenoid is stroking but the en-
gine will not start, it is possible the fuel line has
become filled with air. The possible causes of
a fuel line filled with air are:
Running fuel tank empty before refueling.
n n n n n
Plugged fuel filter.
n n n n n
Loose or broken fuel line connection.
n n n n n
To bleed the air from the fuel lines follow the
procedure outlined. Refer to "Engine Manual"
for illustrations of the parts described.
Unplug the fuel shut-off solenoid (item 30
n n n n n
page 33).
Loosen air vent plugs on the fuel filter sev-
n n n n n
eral turns. Crank the engine until bubbles
do not come out any more. Tighten air vent
plugs.
Loosen air vent plug on top of the fuel in-
n n n n n
jection pump. Crank the engine until
bubbles do not come out anymore. Tighten
air vent plug.
IMPORTANT
Cranking the engine for more than 15
seconds at a time can burn out the fuel
solenoid and can lead to premature
starter failure.
25