replace or not replace
 

I have a 38k jdm donor engine. I have a short block being put together at the machine shop. Is it protocol to go ahead and replace the water pump with a new one when building a new engine, or is it perfectly fine to use the low mileage water pump?

I don't mind spending money on needed items, but I don't want to piss it away either

it's a like a $30 part...

I priced it at 65 from local auto places. Where are you getting your from? I fit's only $30, then I'll just replace it.

ebay of course. Shouldn't be more than $45 at any advance auto parts or equivalent. no way i'd trust a '38K' mileage JDM water pump.

But why spend $30 when it's far more fun to wonder when it's going to crap out on you? I mean, it only has 38k, right? That means it's like almost new. And who wouldn't want to go back in to change it in a couple years when the interval comes up? Yeesh.

Even better, he could contact one of the recyclers and replace it with a USED part for half the price of new and even more mechanical roulette! Clearly replacing an unknown* mileage/age part with another unknown mileage/age part would be a great idea!

*Yeah, you don't really know the mileage or age of that JayDeeEMmmm motor or any of its components. Since you're just using it as a rebuildable core, that's not really an issue, but that's all it should be treated as, a rebuildable core.

Thanks for the input, I'll go ahead and get one ordered.

Any particular brand of ebay pump to get or avoid?

i got mine from seller domesticgaskets....just don't get a head gasket from them.

I got a GMB one off ebay about a month ago. I got the whole timing belt kit for a little less then 100$. The water pump was stamped made in Japan.