Yanmar 2GM20F Raw Water Impeller

[John Galleazzi]

Does anyone have any tips on replacing the raw water impeller on a YAnmar 2GM20F?Getting access to the screws on the impeller housing is a job in of itself, but getting the impeller out is another story. It seems to be held in by some type of screw, but without a mirror I couldn't see what type. Short of standing on my held and bending into impossible contortions, I can't seem to find an eay way of getting access to replace the impeller.Hints and suggestions fromthose who have been there and done that are most appreciated.

 

[Gary Wyngarden]

Raw Water Impeller

John,I'm not sure about your engine and impeller. However, the impeller on the 3gm30f on my 335 is also difficult to access. I have to remove the drive belt and then remove the housing from the engine compartment to aceess the impeller. The plate covering the impeller faces aft toward the engine and there's no other way to get to it. Once removed from the engine compartment, remove the covering plate and pry the impeller from the housing. Don't forget to replace the gasket after you replace the impeller. Hope this helps.Gary WyngardenS/V Shibumi H335

 

[Ralph Johnstone]

Unless the engine has changed ...................

...... drastically over the years and is quite different from our 1999 model, simply remove the suction and discharge hoses, remove the drive belt, and unbolt the pump from its bracket. The pump is now sitting in your lap for the careful internal inspection it deserves.Quite simple really with a few combination wrenches and a screw driver.Hope this helps.Regards,s/v Island Hunter

 

[Bob Fuller]

Raw Water Pump

Shut raw water valve. Remove the hoses, belt, and pump. Take off the backplate(6 screws).Pay attention to the direction that the impeller vanes fold against the housing before removing the old impeller. Make sure the gasket surfaces are clean and smooth. Make sure the backplate is flat(clearance issues=pump capacity).Replace the new impeller(use a little soap to facilitate putting the new impeller in so none of the new vanes are damaged), new gasket, and new screws. Remount pump, reattach hoses and belt, open water valve and start her up. Probably a 30 minute job. Enjoy!