Raw Water Impeller

[gmcc]

I have an inboard ski boat that is going into it's third season with about 90 hours on it. I was wondering when I should think about replacing the raw water impeller. It is Mercruiser 5.7 MAG. I believe in preventive maintance but don't want to do it too soon. Any input would be appreciated.

 

[Don S]

Re: Raw Water Impeller

What drive and what year?

 

[gmcc]

Re: Raw Water Impeller

Don, it is a 2 year old (2006) inboard direct drive (not i/o). I believe the raw water pump runs off the serpentine belt.

 

[Don S]

Re: Raw Water Impeller

If it's a Mercruiser or Volvo engine, I know the type pump it has, and they should be replaced every other year. They have short vanes and take a set easily. Hours isn't everything on an impeller. They have to set all bent over even when not running. After a while, you may have only half of the impeller doing anything.