Yanmar 3G water pump - advice please

[MickeyB]

On the eve (+1) of our annual pilgrimage to Sicily (from base Malta) I notice water underneath the engine.

Check pipes, all good....finally discover it is coming from the water pump.  So I take it out and *shock*!  5 of the 6 bolts have no heads!  How the hell did this not fail earlier?



My biggest question to you all is, any ideas on how this happened?  Electrolysis? Wrong metal?

Time to check everything else out now...

Thanks in advance.

[MalcolmP]

Yes I would suspect both, certainly it is electrolysis, looks like there must have been a lot of salt water in that area - presume you have checked for corrosion elsewhere , esp on wiring looms and connectors.  Have you been able to extract the old screws and get the unit working again? fortunately on newer Yanmar's the waterpump is now at the front of the engine in a more visible place. A speedseal which comes with S/s thumb-bolts may be a useful upgrade