lost a seal in my bone stock--engine mounted water pump today. anyone ever run an aftermarket aluminum water pump. I ran an Edelbrock one on my small block for yrs. In lake michigan, corrosion is not too much of a problem. Is edelbrock still a viable option? and what part number will fit my 502 gen 6 block?

Unless your closed cool using AF, only use a marine water pump

ok, but why? you already have aluminum heads ,intake etc.

in fresh water that gets used for a few months and then winterized i dont see corrosion happening

Aluminum will corroded, just takes longer in fresh water

The issue is corrosion, if your comfortable with the risk then order one from one of the speed shops. They are physically the same size. A lot of boaters are "same for same " the answer your most likely going to get is to replace it with a genuine Mercruiser part. From a car guys point of view a Mercruiser 502 MPI is just a big block Chevy with a crappy fuel injection strapped on it and in the end it takes BBC parts .

Ya but? BBC parts from what generation. If you look at generic Chevy car parts, are they before 1972, short shaft corvette pumps, standard 72-1991 gen part. There are approximately. 10 different BBC water pumps. Or? With an add on Hardin marine stainless housing, will a stock impeller flow enough through a inlet crossover with bypass to keep my manifold cool enough.?

But I can't give you first hand experience, in the end I put a cast iron replacement in my 540 build, the weight isn't an issue. But more importantly I dont want to give you incorrect information. Call Summit or Jegs and get one assuming the rotation is correct. I would assume the exhaust flow will be just fine but thats a guess .

It’s a short-style pump.

And, I’d go for the marine replacement. The impeller is uni-directional and made of stainless. I’ve run an automotive pump (small block) in fresh water and it last two seasons. Replaced with a marine version and to my knowledge it’s still kicking some ten years later.