1998-2004 Yamaha WaveRunner XL700 XL760 XL1200 Factory Service Manual, Page 44Get this manual
'''''1_I_JE_T_P_U_M_P_U_N_I_T_ _C_g_=:_ JET PUMP UNIT Impeller inspection 1Check: ImpellerCD WearDamage ReplaceScratchNick FileGrind2Measure: Impeller clearance Out of specification Replace
Impeller clearance limit: 0.6 mm (0.024 in)
Measurement steps: Remove the battery Remove the intake screen CD Measure the clearance at points Install the intake screen