Mitsubishi 4G1 Service Manual page 486

Roller
Small wire
DOHC
Tip
LASH ADJUSTER LEAK DOWN TEST
Caution
1. The lash adjuster is a precision part. Keep it free from
dust and other foreign matter.
2. Do not disassemble lash adjuster.
3. When cleaning lash adjuster, use clean diesel fuel only.
(2) While lightly pushing down inner steel ball using the small
wire, move the plunger up and down four or five times to
bleed air.
Use of the retainer helps facilitate the air bleeding of the
rocker arm mounted type lash adjuster.
(3) Remove the small wire and press the plunger. If the plunger
is hard to be pushed in, the lash adjuster is normal. If the
plunger can be pushed in all the way readily, bleed the lash
adjuster again and test again. If the plunger is still loose,
replace the lash adjuster.
Caution
Upon completion of air bleeding, hold lash adjuster
upright to prevent inside diesel fuel from spilling.