I potsed a thread earlier and am going to back flush( I sucked up buckets of sand) from the manifolds, take out the engine drains, replace the impellar, replace thermostat, Do you think I should replace the water circulation pump? For $200 i didnt want to do it for nothing ya know. Thanks

Isn't there in impeller in the circulation pump - I would replace that.

^^^^^ What He Said ^^^^^

You can remove the circ pump and then remove the back cover to inspect it. The impeller is metal so, I doubt there is anything wrong with it.

I just had one with a rubber impeller in the circ. pump !!!!

NEVER KNOW ,,i quess .

Why aren't they all made of metal/stainless steel?

Ditto.

I would be more worried about getting the
various coolers ( fuel, p/s, oil)and the ex manifolds cleaned
out good.