[Feetwet]

I have a new to me, 2004 Sovran 4400.  The front head is not flushing and I want to replace the duck bill values  The pump is hard to get to, and I can't find a pump model number.  Can anyone tell from the picture if I should order 1 1/2 or 2" duckbill values.  I see both options available online.   

I also see some pumps have two values, and some have four. This looks like two to me (one each side of pump) 

I am not at the boat to measure the size.  Thanks, Rich 

   

[MC1600]

If it were me, unless someone here is 100% positive, I’d order both sizes and return what you don’t use. In terms of quantity, there should be two on each side of that pump (typically on each end of those black connectors). Look around at the rest of the system too. There are probably some coming out of your pressure tank too.

[Matta0413]

While you have it apart you might as well do the pressure switch too. It is a recommended maintenance part.