Wednesday, December 23, 2020

Refurbishing the engine water pump

The manual says to change the impeller every 1,000 hours (or earlier if an annual inspection shows damage) but like most owners I change the impeller every year, its not an expensive item, the additional work over an inspection is trivial and they have been known to fail after the engine has been unused for an extended period. 

This year however a bit more was required as the end plate was worn and needed replacement (again not expensive) so it seemed sensible to refurbish the unit as necessary and give it a couple of coats of paint after removing corrosion - the body of the pump is bronze and quickly goes green the mounting plate is steel so subject to rust, I chose some silver "Hammerite" that I already had as Yanmar coloured paint is silly money.

Removing crud, inside and out took some time but was a straight forward job that should not needed to be done again for several years.

The impeller was actually OK but was changed anyway.
The end plate was badly scored so also changed. Bearings
and the water seal were fortunately fine and did not have to
be replaced.

Almost ready to go, the liquid on the seal and lubricating
the impeller is Glycerine, oil will damage the rubber impeller.

The paint was redone in November 2023 after the impeller failed after one seasons use.

No comments:

Post a Comment