Yanmar 315 water pump

[sparty12]

Anyone ever rebuild a Yanmar 315 Johnson water pump. Mine is 13 months old and leaking already.

[Maye Marie]

I have rebuilt mine. It is not hard to do. I bought my parts from http://www.depcopump.com. They have all what you need and part kits to chose from. They range form complet rebuild to parshall. Instructions and schematics also. I did a complet rebuild and orderd a partial kit to keep on board for back up. A few youtube showing how to also is on the internet.

Were is it leaking from. Front plate area its just a plate to look at. If back buy the engine then it is a saft seal. To go so quickly I would say it ran dry, sat for a long time dry or vaulty installation of seal. Pay close attention to the slinger washer it needs to be in the right place.

[sparty12]

Thanks----leaking from the slinger washer but not all the time---checked while running and no leaks----bring boat in, shut down
engine and leaks from the weep hole. Only 13 months old.

[Maye Marie]

It sounds like it is leaking through the shaft seal. I would say you will need to pull the pump and disassemble. Here is a link for a you tube showing how to rebuild. https://www.youtube.com/watch?v=Gcx1rHRXAkI

I think he has over done taking it apart with wood jig and press. Use a 3/4 brass rod and hammer to knock out the bearing would be fine. The brass rod is soft enough you wont damage the shaft. Use the brass rode as a punch on the end of the shaft and tap assembly out with hammer. Tape the shaft on one side to mark the bearing distance. Knock bearings off with copper pipe sized to just fit over shaft. Soft copper or brass on the inner race of the bearing will not mar or damage. Put together same way tapping bearing up to your tape for distance. Putting it back together use copper pipe same way tapping bearing back to the tape for distance.