Water pump impeller blades

[Steve Tinker]

Hi Doug - looks like your preventative maintenance is keeping you busy.
As to the damaged impeller, does the damage look like an actual breakage or erosion of the plastic - difficult to see from here. How many miles /years has the pump done? I bet you were losing 25% of your coolant flow looking at the impeller vanes......

If its erosion, there shouldn't be a problem, but if bits have actually snapped off, then the debris could still be in the system. The first place I would look ('cos its easy) is in the thermostat housing to see if the thermostat has stopped the damaged bits from circulating. I think Jeff (JFP in PA) has suggested in the past to "back flush" the system to make sure any loose bits are flushed out before bolting back together - how difficult this is I'm not sure but its probably easier and cheaper than having a coolant blockage in the cylinder heads.

I'm sure one of the professionals with more experience than me will chime in with some good advice...