JLG 340AJ Service Manual - Manual (Page 151)

SECTION 4 - BOOM & PLATFORM
3121259 – JLG Lift – 4-19
7. Install the inner T-seal (200) into the appropriate groove
in the piston (3). Use a circular motion to ensure the seal
is correctly seated in the groove.
Install the outer T-seal (202) by stretching it around the
groove in a circular motion.
Each T-seal has 2 back-up rings (see Assembly Drawing
for orientation). Beginning with the inner seal (200)
insert one end of backup ring in the lower groove and
feed the rest in using a circular motion. Make sure the
wedged ends overlap correctly.
Insert the other back up ring in upper groove.
Repeat both of these steps for the outer seal (202).
8. Insert the piston (3) into the housing (1) as shown, until
the outer piston seal (202) contacts the inside housing
bore.
9. Looking into the housing bore from the shaft flange
end, rotate the piston (3) until the marks you put on the
piston and the housing (1) during disassembly align as
shown. Using a rubber mallet, tap the piston into the
housing until the gear teeth contact.