what water pump is on a 1978 mercruiser 170hp 224cc 3.7 liter
Got no partnumbers but.. the 3.7 is a Ford engine and dont know from your question if you mean the circulation pump on the front of the engine or the raw water pump in the outdrive. This engine has a closed cooling system and uses coolant to cool the engine pumped around by the circ. pump on the engines front. The water to cool the heat exchanger (and so the coolant) is pumped up by the outdrive pump. Mostly when the engine runs hot the outdrive impeller is worn out and need to be changed or the raw water system can be cloged up by debris.
Something in your description doesn't add up. Mercruiser did not have a motor branded as 170 hp in 1978, only 85-86. The 224s where a Mercury invention, all about the same for around 15 years. Do you you have a ser #, much more accurate identification.
