We were recently contracted to supply a C&V Survey on a new (never sold, old stock) 2006 advertised length 46. Here is what we found regarding bilge pumps:
"DEWATERING ASSETS: 12V DC automatic pumps are fitted forward, amidship and aft in each watertight hull compartment. Pumps are discharged into a common manifold carried aft.
Each pump has a bronze, domestic plumbing type one-way check valve incorporated into the discharge line, purpose of which is believed to be to prevent one pump from back feeding into another pump in the manifold system.
The use of check valves is disallowed by ABYC in most installations (with the one exception of preventing cycling of an automatic pump from itís own discharge backflow Ė Rule 22.8.9) and common sense dictates that such devices present a weak point in the most important safety asset of any vessel, by creating blockage in a pumpís discharge line in case of a valve malfunction. ABYC Rule 22.8.8 states: ďA check valve shall not be used in a discharge manifold system.Ē This Rule also states that simultaneous operation of all pumps in a manifold system must not diminish the pumping capacity of the pumps. While the latter may not be an issue (judging by the diameter of the discharge manifold), the vesselís bilgepumping system must be inspected by a qualified technician and reconfigured to compliance with all pertinent ABYC Rules & Regulations (and common sense safety considerations)."
Aside from this, after surveying several dozens of these boats it would appear that they are strong and well built boats.
The one way valves in bilgepumping assets is a no-brainer safety issue that is not hard to understand, and I have no idea why an otherwise intelligent and good builder would not see the reasoning...