[C320-list] Yanmar circulation pump

[Joe M]

3 winters in a row when it is very cold, I would find coolant in engine
pan. Just determined the mystery leak is the weephole on circ pump. When it
gets warm not a drop all spring, summer and fall. Are these pumps known for
this?

I actually have a spare pump. Anyone replace one? Seems the pump is holding
that big housing behind it with t stat and even alternator bracket and
another gasket behind it. That is asking a lot from those water pump bolts.
Or are there bolts behind the pump unseen that is holding that housing to
head/block?

Joe 2002 C320 hull #902