1985 OMC 65, 100 and 155 HP Models Commercial Service Manual, PN 507450-D, Page 391Get this manual
Use the following guide to interpret the current draw readingsThis, together with the symptoms listed in Common Problems should help pinpoint the problem1Normal Current DrawNormal maximum current draw in the full up or full down mode indicates the hydraulic pumpmotor combination and relief valves are functioning to specsThe problem is elsewhere, such as in the pump control piston, malfunctioning check valve, or mechanical binding2Low Current DrawLower than maximum current draw in the ful up or full down mode generally indicates: aLeaking valves bWeak relief valvescdPoor pump performanceLeaking O-rings on valve bodies
3High Current DrawHigher than maximum current draw in either the full up or full down mode indicates: aElectric motor malfunctioning electrically or mechanicalyRemove motor and check for bindingCheck no load current drawPump bindingPump should turn with 0,25 Nm (2.25 in lbsRelief valves not opening at correct pressurec