Kubota ZD18 User Manual

1-S17
ZD25F, WSM
ENGINE
Valve Clearance
IMPORTANT
• The valve clearance must be checked and adjusted when
engine is cold.
1. Remove the cylinder head cover and the glow plugs.
2. Align the “1TC” mark (1) on the flywheel and alignment mark (2)
on the rear end plate so that the No. 1 piston comes to the
compression top dead center.
3. Check the following valve clearance marked with “” using a
feeler gauge.
[When No. 1 piston comes to the compression top dead center]
4. If the clearance is not within the factory specifications, adjust with
the adjusting screw.
5. Then turn the flywheel 6.28 rad (360°), and align the “1TC” mark
(1) on the flywheel and alignment mark (2) on the rear end plate
so that the No. 1 piston comes to the overlap position.
6. Check the following valve clearance marked with “” using a
feeler gauge.
[When No. 1 piston comes to the overlap position]
7. If the clearance is not within the factory specifications, adjust with
the adjusting screw.
NOTE
• The sequence of cylinder numbers is given as No. 1, No. 2
and No. 3 starting from the gear case side.
• After adjusting the valve clearance, secure the adjusting
screw with the lock nut.
W10113200
Cylinder No. No. 1 No. 2 No. 3
Intake valve 
Exhaust valve 
Cylinder No. No. 1 No. 2 No. 3
Intake valve 
Exhaust valve 
Intake and exhaust
valve clearance (Cold)
Factory spec.
0.145 to 0.185 mm
0.00571 to 0.00728 in.
(1) “1TC” Mark
(2) Alignment Mark
A : Gear Case Side
KiSC issued 04, 2009 A

Kubota ZD18 Specifications

General

Horsepower	18 hp
Transmission	Hydrostatic
Cutting Width	48 inches
Drive	2WD
Engine Type	Diesel
Cutting Height Range	4 inches