Suzuki DF25/DF30 Four Stroke Service Manual, Page 132Get this manual
POWER UNIT 7-15 (6) Insert spacer into chain tensionerInstall chain tensioner as shown in figureApply oil to chain tensioner
(7) With latch of tensioner adjuster returned and plunger pushed back into body, insert stopper into latch and bodyAfter inserting stopper, check to make sure that plunger will not come out