The 1000 hr water pump service interval for the Cox 300 calls to me.
The service interval for waterpumps on outboards has always screamed "There has to be a better way".
I would be very interested in knowing the intricacies of the design of their waterpump.
I mainly change my water pump every couple years to ensure I can get the lower unit off. Waited to long on a 9.9 Yami and it was a real bitch to get the lower unit off. Normally the impeller looks fine. If fact between multiple outboards on multiple boats the only impeller issue I have had is a failure 10 hrs after paying to have it done at Master Marine. I was headed to Esperanza Inlet and staying at a remote cabin. I was running short on time before leaving for the trip so took it in for some preventative maintenance. Shortly into the trip the impeller sheared the center collar that holds it to the shaft. I chock it up to improper install since it only lasted a short amount of time before totally destroying itself.
Even if the pump is “Good” for 1000 hours it doesn’t mean the other bolting should not be exercised.