PERIODIC MAINTENANCE82 JH Series Operation ManualChanging the Engine Oil andReplacing the Engine Oil FilterElementSee Changing the Engine Oil andReplacing the Engine Oil Filter Element onpage 72.Changing the Marine Gear Oil andReplacing the Marine Gear Oil FilterElement (if equipped)See Changing the Marine Gear Oil andReplacing the Marine Gear Oil Filter (IfEquipped) on page 73.Checking or Replacing SeawaterPump Impeller1. Loosen side cover bolts and removethe side cover.2. Inspect the inside of the seawaterpump with a flashlight. If any of thefollowing are found, disassembly andmaintenance are required:• Impeller blades are cracked or nicked.Edges or surfaces of the blades aremarred or scratched.• Wear plate is damaged.3. If no damage is found when inspectingthe inside of the pump, install the O-ringand side cover.4. If a large amount of water leakscontinuously from the water drain linebelow the seawater pump duringoperation, replace the mechanical seal.See your authorized Yanmar Marinedealer or distributor.Replacing the Seawater Pump ImpellerNote: The impeller must be replacedperiodically (every 1000 hours)even if there is no damage.Figure 15There are two types of special servicetools for removing the impeller:Puller A (standard)Part No. 129671-92110Figure 161. Remove the side cover of the seawaterpump.2. Install puller (Figure 16, (A)) in theimpeller.3. Turn the jack screw (Figure 16, (B))clockwise to remove the impeller fromthe pump body.Puller A Jack Screw BM18x1.5 M10x40 mm length0004510(1)0004501(B)(A)
