JLG X23J - X700AJ Service Manual - Manual (Page 159)

SECTION 3 - CHASSIS & TURNTABLE
3-132 – JLG Lift – 3121448
SPARK PLUG CHECK/ADJUSTMENT
IF THE ENGINE HAS BEEN RUNNING, THE ENGINE WILL BE VERY
HOT. ALLOW IT TO COOL BEFORE PROCEEDING.
Remove the spark plug cap, and then remove the spark
plug (1) using a spark plug wrench (2).
Visually check the spark plug. Replace the plug if the insu-
lator (1) is cracked or chipped.
Check the sealing washer (2) for damage.
Replace the spark plug if the sealing washer is damaged
(page 3-8).
SPARK PLUG: BPR6ES (NGK) W20EPR-U(DENSO)
Measure the plug gap with a wire-type feeler gauge. If the
measurement is out of the specification, adjust by bend-
ing the side electrode.
PLUG GAP: 0.7 – 0.8 mm (0.028 – 0.031 in)
Install the spark plug finger-tight to seat the washer, and
then tighten 1/8 – 1/4 turn with a spark plug wrench.
A LOOSE SPARK PLUG CAN BECOME VERY HOT AND CAN DAM-
AGE THE ENGINE. OVER TIGHTENING CAN DAMAGE THE
THREADS IN THE CYLINDER BLOCK. INSTALL THE SPARK PLUG
CAP SECURELY.
SPARK PLUG REPLACEMENT
IF THE ENGINE HAS BEEN RUNNING, THE ENGINE WILL BE VERY
HOT.ALLOW IT TO COOL BEFORE PROCEEDING.
Remove the spark plug cap, and then remove the spark
plug (1) using a spark plug wrench (2).
Verify the new spark plug gap is correct (page 3-7).
Install a new spark plug finger-tight to seat the washer,
and then tighten 1/2 turn with a spark plug wrench.
SPARK PLUG: BPR6ES (NGK)W20EPR-U(DENSO)
(1)
(2)
(2)
(1)
0.7 – 0.8 mm
(0.028 – 0.031 in)
(1)
(2)