Suzuki DF25/DF30 Four Stroke Service Manual, Page 250Get this manual
10-26 LOWER UNIT CHECKING DRIVESHAFT THRUST PLAY After obtaining optimum tooth contact, driveshaft thrust play should be measured1Affix gear adjusting gauge to driveshaft09951-09511Gear adjusting gauge 2Slowly push driveshaft downwardRead the maximum playDesignate this amount of play as (A)Driveshaft thrust playApprox0.20 0.40 mm (0.008 0.016 in
NOTE: Driveshaft thrust play (A) must be known to adjust reverse gear shimRECHECKING DRIVESHAFT THRUST PLAYReverse gear back-up shim adjustment1After adjusting forward gear tooth contact pattern, correctly assemble propeller shaft, housing assembly, reverse gear and related components (see page 10-16 to 10-17)